diff --git a/package.json b/package.json
index db02e7b2b2..c1bd554fbb 100644
--- a/package.json
+++ b/package.json
@@ -41,6 +41,7 @@
     "@reduxjs/toolkit": "^1.9.7",
     "@sentry/react": "^10.5.0",
     "@sourceacademy/c-slang": "^1.0.21",
+    "@sourceacademy/language-directory": "https://github.com/loyaltypollution/language-directory.git#866cc934372a19e514af0025947ce7f1f5a6e1fc",
     "@sourceacademy/sharedb-ace": "2.1.1",
     "@sourceacademy/sling-client": "^0.1.0",
     "@szhsin/react-menu": "^4.0.0",
@@ -67,7 +68,6 @@
     "js-slang": "^1.0.85",
     "js-yaml": "^4.1.0",
     "konva": "^9.2.0",
-    "language-directory": "https://github.com/source-academy/language-directory.git",
     "lodash": "^4.17.21",
     "lz-string": "^1.4.4",
     "mdast-util-from-markdown": "^2.0.0",
diff --git a/public/evaluators/pie-slang/pie.js b/public/evaluators/pie-slang/pie.js
new file mode 100644
index 0000000000..b5c084a0fe
--- /dev/null
+++ b/public/evaluators/pie-slang/pie.js
@@ -0,0 +1,2 @@
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This should never happen.");if(1===t.length){const n=t[0];if(j(n))return n;if((e=n).type!==G.IDENTIFIER&&e.type!==G.NUMBER&&e.type!==G.STRING&&e.type!==G.BOOLEAN)throw new Q("",n.pos,n,"<data>");return new K(t)}var e;if(2===t.length){const e=t[0];if(Y(e)&&function(t){return t.type===G.APOSTROPHE||t.type===G.BACKTICK||t.type===G.HASH_VECTOR||t.type===G.COMMA||t.type===G.COMMA_AT}(e))return new K(t)}const n=t[0],r=t[t.length-1];if(Y(n)&&Y(r)&&(i=r,(s=n).type===G.LEFT_PAREN&&i.type===G.RIGHT_PAREN||s.type===G.LEFT_BRACKET&&i.type===G.RIGHT_BRACKET))return new K(t);var s,i;const a=new K(t);throw new Q("",a.location.start,a,"matching parentheses")}first(){return this.elements[0]}firstToken(){const t=this.first();return Y(t)?t:t.firstToken()}firstPos(){return this.firstToken().pos}last(){return this.elements[this.elements.length-1]}lastToken(){const t=this.last();return Y(t)?t:t.lastToken()}lastPos(){return this.lastToken().pos}isParenthesized(){const t=this.first();return 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q(t.pos,t.endPos)}destructureList(t,e=t=>{}){if(0===t.length)return[[],void 0];if(1===t.length)return e(t[0]),[[this.parseExpression(t[0])],void 0];const n=t.at(-2);if(Y(n)&&n.type===G.DOT){const n=t.at(-1),r=t.slice(0,-2);return e(n),r.forEach(e),[r.map(this.parseExpression.bind(this)),this.parseExpression(n)]}const r=t;return r.forEach(e),[r.map(this.parseExpression.bind(this)),void 0]}grouping(t){const e=[];let n=!1;t&&(n=!0,e.push(t));do{const t=this.advance();switch(t.type){case G.LEFT_PAREN:case G.LEFT_BRACKET:const r=this.grouping(t);e.push(r);break;case G.RIGHT_PAREN:case G.RIGHT_BRACKET:if(!n)throw new F(this.source,t.pos,t);e.push(t),n=!1;break;case G.APOSTROPHE:case G.BACKTICK:case G.COMMA:case G.COMMA_AT:case G.HASH_VECTOR:let s;do{s=this.grouping()}while(!s);e.push(this.affect(t,s));break;case G.QUOTE:case G.QUASIQUOTE:case G.UNQUOTE:case G.UNQUOTE_SPLICING:case G.IDENTIFIER:case G.NUMBER:case G.BOOLEAN:case G.STRING:case G.DOT:case G.DEFINE:case G.IF:case G.ELSE:case 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$t(t){return!("U"===(e=t)||"Nat"===e||"zero"===e||"add1"===e||"which-Nat"===e||"iter-Nat"===e||"rec-Nat"===e||"ind-Nat"===e||"->"===e||"→"===e||"Π"===e||"λ"===e||"Pi"===e||"∏"===e||"lambda"===e||"quote"===e||"Atom"===e||"car"===e||"cdr"===e||"cons"===e||"Σ"===e||"Sigma"===e||"Pair"===e||"Trivial"===e||"sole"===e||"List"===e||"::"===e||"nil"===e||"rec-List"===e||"ind-List"===e||"Absurd"===e||"ind-Absurd"===e||"="===e||"same"===e||"replace"===e||"trans"===e||"cong"===e||"symm"===e||"ind-="===e||"Vec"===e||"vecnil"===e||"vec::"===e||"head"===e||"tail"===e||"ind-Vec"===e||"Either"===e||"left"===e||"right"===e||"ind-Either"===e||"TODO"===e||"the"===e)&&isNaN(Number(t));var e}function St(t){return Array.from(t.keys())}function Ot(t,e){return wt(St(t),e)}function Lt(t,e,n){return wt(St(t).concat(e.findNames()),n)}function At(t){return[t.binder.varName].concat(t.type.findNames())}function It(t,e,n){return new Map([...t,[e,n]])}function Ct(t,e){return e.valOf(Mt(t))}function Bt(t){const e=new Map;for(const[n,r]of t)r instanceof Dt?e.set(n,["free",r.type.readBackType(t)]):r instanceof zt?e.set(n,["def",r.type.readBackType(t),se(t,r.type,r.value)]):r instanceof Ht&&e.set(n,["claim",r.type.readBackType(t)]);return e}function Rt(t,e,n,r){const s=new bt("typeOut");return Nt([[new bt("_"),()=>function(t,e,n){return t.has(n)?new Tt(e,new vt([`The name "${n}" is already in use in the context.`])):new Pt(!0)}(t,n,e)],[s,()=>r.isType(t,new Map)]],()=>new Pt(It(t,e,new Ht(Ct(t,s.value)))))}function qt(t,e,n,r){const s=new bt("typeOut"),i=new bt("exprOut");return Nt([[s,()=>function(t,e,n){for(const[r,s]of t)if(r===n){if(s instanceof zt)return new Tt(e,new vt([`The name "${n}" is already defined.`]));if(s instanceof Ht)return new Pt(s.type)}return new Tt(e,new vt([`No claim: ${n}`]))}(t,n,e)],[i,()=>r.check(t,new Map,s.value)]],()=>new Pt(function(t,e,n,r){return It(t,e,new zt(n,r))}(function(t,e){return t.delete(e),t}(t,e),e,s.value,Ct(t,i.value))))}function Mt(t){if(0===t.size)return new Map;const e=t.entries(),n=new Map;for(const[t,r]of e)r instanceof zt?n.set(t,r.value):r instanceof Dt&&n.set(t,new tn(r.type,new oe(t)));return n}const Gt=new Map;class Ut{}let Ht=class extends Ut{type;constructor(t){super(),this.type=t}};class zt extends Ut{type;value;constructor(t,e){super(),this.type=t,this.value=e}}class Dt extends Ut{type;constructor(t){super(),this.type=t}}function Ft(t,e,n){if(0===t.size)throw new Error(`The context ${JSON.stringify(t)} is empty, but we are looking for ${n}`);for(const[e,r]of t.entries())if(!(r instanceof Ht)&&n===e)return new Pt(r.type);throw new Error(`Unknown variable ${n}`)}function Qt(t,e,n){if(t.has(e)){for(const[r,s]of t)if(r===e)return It(t,e,new Dt(n));throw new Error(`\n      ${e} is already bound in ${JSON.stringify(t)}\n    `)}return It(t,e,new Dt(n))}function Vt(t,e){const n=t.now();if(n instanceof Ue)return n.body.valOfClosure(e);if(n instanceof tn){const t=n.type.now();if(t instanceof Ge)return new tn(t.resultType.valOfClosure(e),new Oe(n.neutral,new ie(t.argType,e)))}throw new Error(`doApp: invalid input ${[n,e]}`)}function Xt(t,e,n,r){const s=t.now();if(s instanceof qe)return n;if(s instanceof Me)return Vt(r,Xt(s.smaller,e,n,r));if(s instanceof tn){if(s.type.now()instanceof Re)return new tn(e,new he(s.neutral,new ie(e,n),new ie(new Ge("n",new Re,new kt(t=>e)),r)))}throw new Error(`invalid input for iterNat ${[t,e,n,r]}`)}function Kt(t,e,n,r){const s=t.now();if(s instanceof qe)return n;if(s instanceof Me)return Vt(Vt(r,s.smaller),Kt(s.smaller,e,n,r));if(s instanceof tn){if(s.type.now()instanceof Re)return new tn(e,new le(s.neutral,new ie(e,n),new ie(new Ge("n-1",new Re,new kt(t=>new Ge("ih",e,new kt(t=>e)))),r)))}throw new Error(`invalid input for recNat ${[t,e,n,r]}`)}function Yt(t,e,n,r){const s=t.now();if(s instanceof qe)return n;if(s instanceof Me)return Vt(Vt(r,s.smaller),Yt(s.smaller,e,n,r));if(s instanceof tn){if(s.type.now()instanceof Re)return new tn(Vt(e,t),new pe(s.neutral,new ie(new Ge("x",new Re,new kt(t=>new en)),e),new ie(Vt(e,new qe),n),new ie(new Ge("n-1",new Re,new kt(t=>new Ge("ih",Vt(e,t),new kt(n=>Vt(e,new Me(t)))))),r)))}throw new Error(`invalid input for indNat ${[t,e,n,r]}`)}function jt(t){const e=t.now();if(e instanceof ze)return e.car;if(e instanceof tn){const t=e.type.now();if(t instanceof He){const n=t,r=e.neutral;return new tn(n.carType,new we(r))}}throw new Error(`invalid input for car ${t}`)}function Zt(t){const e=t.now();if(e instanceof ze)return e.cdr;if(e instanceof tn){const n=e.type.now();if(n instanceof He){const r=n,s=e.neutral;return new tn(r.cdrType.valOfClosure(jt(t)),new fe(s))}}throw new Error(`invalid input for cdr ${t}`)}function Wt(t,e,n,r){const s=t.now();if(s instanceof Fe)return n;if(s instanceof Qe)return Vt(Vt(Vt(r,s.head),s.tail),Wt(s.tail,e,n,r));if(s instanceof tn){const i=s.type.now();if(i instanceof De){const a=i.entryType,o=s.neutral,c=new Ge("xs",new De(a),new kt(t=>new en));return new tn(Vt(e,t),new de(o,new ie(c,e),new ie(Vt(e,new Fe),n),new ie(new Ge("h",a,new kt(t=>new Ge("t",new De(a),new kt(n=>new Ge("ih",Vt(e,n),new kt(r=>Vt(e,new Qe(t,n)))))))),r)))}}throw new Error(`invalid input for indList ${[s,e,n,r]}`)}function Jt(t,e,n,r){const s=t.now();if(s instanceof Fe)return n;if(s instanceof Qe){const t=s.head,i=s.tail;return Vt(Vt(Vt(r,t),i),Jt(i,e,n,r))}if(s instanceof tn){const t=s.type.now();if(t instanceof De){const i=t.entryType,a=s.neutral;return new tn(e,new ye(a,new ie(e,n),new ie(new Ge("h",i,new kt(t=>new Ge("t",new De(i),new kt(t=>new Ge("ih",e,new kt(t=>e)))))),r)))}}throw new Error(`invalid input for recList ${[s,e,n,r]}`)}function te(t){const e=t.now();if(e instanceof je)return e.tail;if(e instanceof tn&&e.type.now()instanceof Ke&&e.type.now().length.now()instanceof Me){const t=e.type.now();if(t instanceof Ke){if(t.length.now()instanceof Me)return new tn(new Ke(e.type.now().entryType,e.type.now().length.now().smaller),new _e(e.neutral))}}throw new Error(`invalid input for tail ${t.prettyPrint()}`)}function ee(t,e){return new Ge("k",new Re,new kt(n=>new Ge("e",t,new kt(r=>new Ge("es",new Ke(t,n),new kt(t=>new Ge("ih",Vt(Vt(e,n),t),new kt(s=>Vt(Vt(e,new Me(n)),new je(r,t))))))))))}function ne(t,e,n,r,s){const i=t.now(),a=e.now();if(i instanceof qe&&a instanceof Ye)return r;if(i instanceof Me&&a instanceof je)return Vt(Vt(Vt(Vt(s,i.smaller),a.head),te(e)),ne(i.smaller,a.tail,n,r,s));if(i instanceof tn&&a instanceof tn&&i.type.now()instanceof Re&&a.type.now()instanceof Ke){const o=a.type.now().entryType;return new tn(Vt(Vt(n,t),e),new $e(i.neutral,a.neutral,new ie(new Ge("k",new Re,new kt(t=>new Ge("es",new Ke(o,t),new kt(t=>new en)))),n),new ie(Vt(Vt(n,new qe),new Ye),r),new ie(ee(a.type.now().entryType,n),s)))}if(re(i,t)&&a instanceof tn&&a.type.now()instanceof Ke){const i=a.type.now().entryType;return new tn(Vt(Vt(n,t),e),new ke(new ie(new Re,t),a.neutral,new ie(new Ge("k",new Re,new kt(t=>new Ge("es",new Ke(i,t),new kt(t=>new en)))),n),new ie(Vt(Vt(n,new Re),new Ye),r),new ie(ee(i,n),s)))}throw new Error(`invalid input for indVec ${[t,e,n,r,s]}`)}function re(t,e){const n=t.now(),r=e.now();return n instanceof qe&&r instanceof qe||n instanceof Me&&r instanceof Me&&re(n.smaller,r.smaller)}function se(t,e,n){const r=e.now(),s=n.now();if(r instanceof en)return n.readBackType(t);if(r instanceof Re&&s instanceof qe)return new ln;if(r instanceof Re&&s instanceof Me)return new pn(se(t,new Re,s.smaller));if(r instanceof Ge){const e=Ot(t,s instanceof Ue?s.argName:r.argName);return new gn(e,se(Qt(t,e,r.argType),r.resultType.valOfClosure(new tn(r.argType,new oe(e))),Vt(s,new tn(r.argType,new oe(e)))))}if(r instanceof He){const e=jt(n),s=Zt(n);return new Tn(se(t,r.carType,e),se(t,r.cdrType.valOfClosure(e),s))}if(r instanceof nn&&s instanceof Be)return new En(s.name);if(r instanceof rn)return new Ln;if(r instanceof De&&s instanceof Fe)return new _n;if(r instanceof De&&s instanceof Qe)return new Tn(se(t,r.entryType,s.head),se(t,new De(r.entryType),s.tail));if(r instanceof an&&s instanceof tn)return new cn(new An,s.neutral.readBackNeutral(t));if(r instanceof Ve&&s instanceof Xe)return new Bn(se(t,r.type,s.value));if(r instanceof Ke&&r.length.now()instanceof qe&&s instanceof Ye)return new Dn;if(r instanceof Ke&&r.length.now()instanceof Me&&s instanceof je)return r.length.now(),new zn(se(t,r.entryType,s.head),se(t,new Ke(r.entryType,r.length.now().smaller),s.tail));if(r instanceof Ze&&s instanceof We)return new Kn(se(t,r.leftType,s.value));if(r instanceof Ze&&s instanceof Je)return new Yn(se(t,r.rightType,s.value));if(s instanceof tn)return s.neutral.readBackNeutral(t);throw new Error(`Cannot read back ${s.prettyPrint()} : ${r.prettyPrint()}`)}class ie{type;value;constructor(t,e){this.type=t,this.value=e}}let ae=class{constructor(){}toString(){return this.prettyPrint()}};class oe extends ae{name;constructor(t){super(),this.name=t}readBackNeutral(t){return new Jn(this.name)}prettyPrint(){return`N-${this.name}`}}let ce=class extends ae{where;type;constructor(t,e){super(),this.where=t,this.type=e}readBackNeutral(t){return new Zn(this.where,this.type.readBackType(t))}prettyPrint(){return"N-TODO"}},ue=class extends ae{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}readBackNeutral(t){return new wn(this.target.readBackNeutral(t),new cn(this.base.type.readBackType(t),se(t,this.base.type,this.base.value)),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-WhichNat"}},he=class extends ae{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}readBackNeutral(t){return new fn(this.target.readBackNeutral(t),new cn(this.base.type.readBackType(t),se(t,this.base.type,this.base.value)),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-IterNat"}},le=class extends ae{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}readBackNeutral(t){return new yn(this.target.readBackNeutral(t),new cn(this.base.type.readBackType(t),se(t,this.base.type,this.base.value)),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-RecNat"}},pe=class extends ae{target;motive;base;step;constructor(t,e,n,r){super(),this.target=t,this.motive=e,this.base=n,this.step=r}readBackNeutral(t){return new dn(this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-IndNat"}},we=class extends ae{target;constructor(t){super(),this.target=t}readBackNeutral(t){return new bn(this.target.readBackNeutral(t))}prettyPrint(){return"N-Car"}},fe=class extends ae{target;constructor(t){super(),this.target=t}readBackNeutral(t){return new Nn(this.target.readBackNeutral(t))}prettyPrint(){return"N-Cdr"}},ye=class extends ae{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}readBackNeutral(t){return new $n(this.target.readBackNeutral(t),new cn(this.base.type.readBackType(t),se(t,this.base.type,this.base.value)),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-RecList"}},de=class extends ae{target;motive;base;step;constructor(t,e,n,r){super(),this.target=t,this.motive=e,this.base=n,this.step=r}readBackNeutral(t){return new Sn(this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-IndList"}},me=class extends ae{target;motive;constructor(t,e){super(),this.target=t,this.motive=e}readBackNeutral(t){return new In(new cn(new An,this.target.readBackNeutral(t)),se(t,this.motive.type,this.motive.value))}prettyPrint(){return"N-IndAbsurd"}},ge=class extends ae{target;motive;base;constructor(t,e,n){super(),this.target=t,this.motive=e,this.base=n}readBackNeutral(t){return new Rn(this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value))}prettyPrint(){return"N-Replace"}};class ve extends ae{target1;target2;constructor(t,e){super(),this.target1=t,this.target2=e}readBackNeutral(t){return new qn(this.target1.readBackNeutral(t),se(t,this.target2.type,this.target2.value))}prettyPrint(){return"N-Trans1"}}class Ee extends ae{target1;target2;constructor(t,e){super(),this.target1=t,this.target2=e}readBackNeutral(t){return new qn(se(t,this.target1.type,this.target1.value),this.target2.readBackNeutral(t))}prettyPrint(){return"N-Trans2"}}class Pe extends ae{target1;target2;constructor(t,e){super(),this.target1=t,this.target2=e}readBackNeutral(t){return new qn(this.target1.readBackNeutral(t),this.target2.readBackNeutral(t))}prettyPrint(){return"N-Trans12"}}let Te=class extends ae{target;func;constructor(t,e){super(),this.target=t,this.func=e}readBackNeutral(t){const e=this.func.type;if(e instanceof Ge){const n=e.resultType;return new Mn(this.target.readBackNeutral(t),n.valOfClosure(new an).readBackType(t),se(t,this.func.type,this.func.value))}throw new Error("Cong applied to non-Pi type.")}prettyPrint(){return"N-Cong"}},be=class extends ae{target;constructor(t){super(),this.target=t}readBackNeutral(t){return new Gn(this.target.readBackNeutral(t))}prettyPrint(){return"N-Symm"}},Ne=class extends ae{target;motive;base;constructor(t,e,n){super(),this.target=t,this.motive=e,this.base=n}readBackNeutral(t){return new Un(this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value))}prettyPrint(){return"N-IndEqual"}},xe=class extends ae{target;constructor(t){super(),this.target=t}readBackNeutral(t){return new Fn(this.target.readBackNeutral(t))}prettyPrint(){return"N-Head"}},_e=class extends ae{target;constructor(t){super(),this.target=t}readBackNeutral(t){return new Qn(this.target.readBackNeutral(t))}prettyPrint(){return"N-Tail"}};class ke extends ae{length;target;motive;base;step;constructor(t,e,n,r,s){super(),this.length=t,this.target=e,this.motive=n,this.base=r,this.step=s}readBackNeutral(t){return new Vn(se(t,this.length.type,this.length.value),this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-IndVec2"}}class $e extends ae{length;target;motive;base;step;constructor(t,e,n,r,s){super(),this.length=t,this.target=e,this.motive=n,this.base=r,this.step=s}readBackNeutral(t){return new Vn(this.length.readBackNeutral(t),this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.base.type,this.base.value),se(t,this.step.type,this.step.value))}prettyPrint(){return"N-IndVec12"}}let Se=class extends ae{target;motive;baseLeft;baseRight;constructor(t,e,n,r){super(),this.target=t,this.motive=e,this.baseLeft=n,this.baseRight=r}readBackNeutral(t){return new jn(this.target.readBackNeutral(t),se(t,this.motive.type,this.motive.value),se(t,this.baseLeft.type,this.baseLeft.value),se(t,this.baseRight.type,this.baseRight.value))}prettyPrint(){return"N-IndEither"}},Oe=class extends ae{operator;operand;constructor(t,e){super(),this.operator=t,this.operand=e}readBackNeutral(t){return new Wn(this.operator.readBackNeutral(t),se(t,this.operand.type,this.operand.value))}prettyPrint(){return"N-Application"}};class Le{now(){return this}}class Ae{env;expr;constructor(t,e){this.env=t,this.expr=e}undelay(){return this.expr.valOf(this.env).now()}toString(){return`DelayClosure(${this.env}, ${this.expr})`}}class Ie{content;constructor(t){this.content=t}get(){return this.content}set(t){this.content=t}}class Ce extends Le{val;constructor(t){super(),this.val=t}now(){const t=this.val.get();if(t instanceof Ae){const e=t.undelay();return this.val.set(e),e}return t}readBackType(t){return this.now().readBackType(t)}prettyPrint(){return this.now().prettyPrint()}toString(){return`Delay(${this.val})`}}let Be=class extends Le{name;constructor(t){super(),this.name=t}readBackType(t){throw new Error("No readBackType for Quote.")}prettyPrint(){return`'${this.name}`}toString(){return this.prettyPrint()}},Re=class extends Le{constructor(){super()}readBackType(t){return new hn}prettyPrint(){return"Nat"}toString(){return this.prettyPrint()}},qe=class extends Le{constructor(){super()}readBackType(t){throw new Error("No readBackType for Zero.")}prettyPrint(){return"zero"}toString(){return this.prettyPrint()}},Me=class extends Le{smaller;constructor(t){super(),this.smaller=t}readBackType(t){throw new Error("No readBackType for Add1.")}prettyPrint(){return`(add1 ${this.smaller.prettyPrint()})`}toString(){return this.prettyPrint()}},Ge=class extends Le{argName;argType;resultType;constructor(t,e,n){super(),this.argName=t,this.argType=e,this.resultType=n}readBackType(t){const e=this.argType.readBackType(t),n=Ot(t,this.argName),r=Qt(t,n,this.argType);return new mn(n,e,this.resultType.valOfClosure(new tn(this.argType,new oe(n))).readBackType(r))}prettyPrint(){return`(Π ${this.argName} ${this.argType.prettyPrint()} ${this.resultType.prettyPrint()})`}toString(){return this.prettyPrint()}},Ue=class extends Le{argName;body;constructor(t,e){super(),this.argName=t,this.body=e}readBackType(t){throw new Error("No readBackType for Lambda.")}prettyPrint(){return`(lambda ${this.argName} ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}},He=class extends Le{carName;carType;cdrType;constructor(t,e,n){super(),this.carName=t,this.carType=e,this.cdrType=n}readBackType(t){const e=this.carType.readBackType(t),n=Ot(t,this.carName),r=Qt(t,n,this.carType);return new Pn(n,e,this.cdrType.valOfClosure(new tn(this.carType,new oe(n))).readBackType(r))}prettyPrint(){return`(Σ ${this.carName} ${this.carType.prettyPrint()} ${this.cdrType.prettyPrint()})`}toString(){return this.prettyPrint()}},ze=class extends Le{car;cdr;constructor(t,e){super(),this.car=t,this.cdr=e}readBackType(t){throw new Error("No readBackType for Cons.")}prettyPrint(){return`(cons ${this.car.prettyPrint()} ${this.cdr.prettyPrint()})`}toString(){return this.prettyPrint()}},De=class extends Le{entryType;constructor(t){super(),this.entryType=t}readBackType(t){return new kn(this.entryType.readBackType(t))}prettyPrint(){return`(List ${this.entryType.prettyPrint()})`}toString(){return this.prettyPrint()}},Fe=class extends Le{constructor(){super()}readBackType(t){throw new Error("No readBackType for Nil.")}prettyPrint(){return"nil"}toString(){return this.prettyPrint()}},Qe=class extends Le{head;tail;constructor(t,e){super(),this.head=t,this.tail=e}readBackType(t){throw new Error("No readBackType for ListCons.")}prettyPrint(){return`(:: ${this.head.prettyPrint()} ${this.tail.prettyPrint()})`}toString(){return this.prettyPrint()}},Ve=class extends Le{type;from;to;constructor(t,e,n){super(),this.type=t,this.from=e,this.to=n}readBackType(t){return new Cn(this.type.readBackType(t),se(t,this.type,this.from),se(t,this.type,this.to))}prettyPrint(){return`(= ${this.type.prettyPrint()} ${this.from.prettyPrint()} ${this.to.prettyPrint()})`}toString(){return this.prettyPrint()}},Xe=class extends Le{value;constructor(t){super(),this.value=t}readBackType(t){throw new Error("No readBackType for Same.")}prettyPrint(){return`(same ${this.value.prettyPrint()})`}toString(){return this.prettyPrint()}},Ke=class extends Le{entryType;length;constructor(t,e){super(),this.entryType=t,this.length=e}readBackType(t){return new Hn(this.entryType.readBackType(t),se(t,new Re,this.length))}prettyPrint(){return`(Vec ${this.entryType.prettyPrint()} ${this.length.prettyPrint()})`}},Ye=class extends Le{constructor(){super()}readBackType(t){throw new Error("No readBackType for VecNil.")}prettyPrint(){return"vecnil"}toString(){return this.prettyPrint()}},je=class extends Le{head;tail;constructor(t,e){super(),this.head=t,this.tail=e}readBackType(t){throw new Error("No readBackType for VecCons.")}prettyPrint(){return`(vec:: ${this.head.prettyPrint()} ${this.tail.prettyPrint()})`}toString(){return this.prettyPrint()}},Ze=class extends Le{leftType;rightType;constructor(t,e){super(),this.leftType=t,this.rightType=e}readBackType(t){return new Xn(this.leftType.readBackType(t),this.rightType.readBackType(t))}prettyPrint(){return`(Either ${this.leftType.prettyPrint()} ${this.rightType.prettyPrint()})`}toString(){return this.prettyPrint()}},We=class extends Le{value;constructor(t){super(),this.value=t}readBackType(t){throw new Error("No readBackType for Left.")}prettyPrint(){return`(left ${this.value.prettyPrint()})`}toString(){return this.prettyPrint()}},Je=class extends Le{value;constructor(t){super(),this.value=t}readBackType(t){throw new Error("No readBackType for Right.")}prettyPrint(){return`(right 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An}prettyPrint(){return"Absurd"}toString(){return this.prettyPrint()}};class on{toLazy(t){return new Ce(new Ie(new Ae(t,this)))}}let cn=class extends on{type;expr;constructor(t,e){super(),this.type=t,this.expr=e}valOf(t){return this.expr.valOf(t)}prettyPrint(){return`(the ${this.type.prettyPrint()} ${this.expr.prettyPrint()})`}toString(){return this.prettyPrint()}},un=class extends on{valOf(t){return new en}prettyPrint(){return"U"}toString(){return this.prettyPrint()}},hn=class extends on{valOf(t){return new Re}prettyPrint(){return"Nat"}toString(){return this.prettyPrint()}},ln=class extends on{valOf(t){return new qe}prettyPrint(){return"0"}toString(){return this.prettyPrint()}},pn=class extends on{n;constructor(t){super(),this.n=t}valOf(t){return new Me(this.n.toLazy(t))}prettyPrint(){const t=Number(this.n.prettyPrint());return isNaN(t)?`(add1 ${this.n.prettyPrint()})`:`${t+1}`}toString(){return this.prettyPrint()}},wn=class extends on{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}valOf(t){return function(t,e,n,r){const s=t.now();if(s instanceof qe)return n;if(s instanceof Me)return Vt(r,s.smaller);if(s instanceof tn&&s.type.now()instanceof Re)return new tn(e,new ue(s.neutral,new ie(e,n),new ie(new Ge("n",new Re,new kt(t=>e)),r)));throw new Error(`invalid input for whichNat ${[t,e,n,r]}`)}(this.target.toLazy(t),this.base.type.toLazy(t),this.base.expr.toLazy(t),this.step.toLazy(t))}prettyPrint(){return`(which-Nat ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}},fn=class extends on{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}valOf(t){return Xt(this.target.toLazy(t),this.base.type.toLazy(t),this.base.expr.toLazy(t),this.step.toLazy(t))}prettyPrint(){return`(iter-Nat ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n 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on{name;type;body;constructor(t,e,n){super(),this.name=t,this.type=e,this.body=n}valOf(t){const e=this.type.toLazy(t);return new Ge(this.name,e,new _t(t,this.name,this.body))}prettyPrint(){return`(Π (${this.name} ${this.type.prettyPrint()}) \n          ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}},gn=class extends on{param;body;constructor(t,e){super(),this.param=t,this.body=e}valOf(t){return new Ue(this.param,new _t(t,this.param,this.body))}prettyPrint(){return`(λ (${this.param}) ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}},vn=class extends on{valOf(t){return new nn}prettyPrint(){return"Atom"}toString(){return this.prettyPrint()}},En=class extends on{sym;constructor(t){super(),this.sym=t}valOf(t){return new Be(this.sym)}prettyPrint(){return`'${this.sym}`}toString(){return this.prettyPrint()}},Pn=class extends on{name;type;body;constructor(t,e,n){super(),this.name=t,this.type=e,this.body=n}valOf(t){const e=this.type.toLazy(t);return new He(this.name,e,new _t(t,this.name,this.body))}prettyPrint(){return`(Σ (${this.name} ${this.type.prettyPrint()}) \n              ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}},Tn=class extends on{first;second;constructor(t,e){super(),this.first=t,this.second=e}valOf(t){const e=this.first.toLazy(t),n=this.second.toLazy(t);return new ze(e,n)}prettyPrint(){return`(cons ${this.first.prettyPrint()} ${this.second.prettyPrint()})`}toString(){return this.prettyPrint()}},bn=class extends on{pair;constructor(t){super(),this.pair=t}valOf(t){return jt(this.pair.toLazy(t))}prettyPrint(){return`(car ${this.pair.prettyPrint()})`}toString(){return this.prettyPrint()}},Nn=class extends on{pair;constructor(t){super(),this.pair=t}valOf(t){return Zt(this.pair.toLazy(t))}prettyPrint(){return`(cdr ${this.pair.prettyPrint()})`}toString(){return this.prettyPrint()}},xn=class extends on{head;tail;constructor(t,e){super(),this.head=t,this.tail=e}valOf(t){const e=this.head.toLazy(t),n=this.tail.toLazy(t);return new Qe(e,n)}prettyPrint(){return`(:: ${this.head.prettyPrint()} ${this.tail.prettyPrint()})`}toString(){return this.prettyPrint()}},_n=class extends on{valOf(t){return new Fe}prettyPrint(){return"nil"}toString(){return this.prettyPrint()}},kn=class extends on{elemType;constructor(t){super(),this.elemType=t}valOf(t){return new De(this.elemType.toLazy(t))}prettyPrint(){return`(List ${this.elemType.prettyPrint()})`}toString(){return this.prettyPrint()}},$n=class extends on{target;base;step;constructor(t,e,n){super(),this.target=t,this.base=e,this.step=n}valOf(t){return Jt(this.target.toLazy(t),this.base.type.toLazy(t),this.base.expr.toLazy(t),this.step.toLazy(t))}prettyPrint(){return`(rec-List ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}},Sn=class extends on{target;motive;base;step;constructor(t,e,n,r){super(),this.target=t,this.motive=e,this.base=n,this.step=r}valOf(t){return Wt(this.target.toLazy(t),this.motive.toLazy(t),this.base.toLazy(t),this.step.toLazy(t))}prettyPrint(){return`(ind-List ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}},On=class extends on{valOf(t){return new rn}prettyPrint(){return"Trivial"}toString(){return this.prettyPrint()}},Ln=class extends on{valOf(t){return new sn}prettyPrint(){return"sole"}toString(){return this.prettyPrint()}},An=class extends on{valOf(t){return new an}prettyPrint(){return"Absurd"}toString(){return this.prettyPrint()}},In=class extends on{target;motive;constructor(t,e){super(),this.target=t,this.motive=e}valOf(t){return function(t,e){const n=t.now();if(n instanceof tn&&n.type.now()instanceof an)return new tn(e,new me(n.neutral,new ie(new en,e)));throw new Error(`invalid input for indAbsurd ${[t,e]}`)}(this.target.toLazy(t),this.motive.toLazy(t))}prettyPrint(){return`(ind-Absurd \n              ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()})`}toString(){return this.prettyPrint()}},Cn=class extends on{type;left;right;constructor(t,e,n){super(),this.type=t,this.left=e,this.right=n}valOf(t){return new Ve(this.type.toLazy(t),this.left.toLazy(t),this.right.toLazy(t))}prettyPrint(){return`(= ${this.type.prettyPrint()} \n              ${this.left.prettyPrint()} \n              ${this.right.prettyPrint()})`}toString(){return this.prettyPrint()}},Bn=class extends on{type;constructor(t){super(),this.type=t}valOf(t){return new Xe(this.type.toLazy(t))}prettyPrint(){return`(same ${this.type.prettyPrint()})`}toString(){return this.prettyPrint()}},Rn=class extends on{target;motive;base;constructor(t,e,n){super(),this.target=t,this.motive=e,this.base=n}valOf(t){return function(t,e,n){const r=t.now();if(r instanceof Xe)return n;if(r instanceof tn){const t=r.type.now();if(t instanceof Ve){const s=r.neutral,i=t.type,a=t.from,o=t.to;return new tn(Vt(e,o),new ge(s,new ie(new Ge("x",i,new kt(t=>new en)),e),new ie(Vt(e,a),n)))}}throw new Error(`invalid input for replace ${[t,e,n]}`)}(this.target.toLazy(t),this.motive.toLazy(t),this.base.toLazy(t))}prettyPrint(){return`(replace ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()})`}toString(){return this.prettyPrint()}},qn=class extends on{left;right;constructor(t,e){super(),this.left=t,this.right=e}valOf(t){return function(t,e){const n=t.now(),r=e.now();if(n instanceof Xe&&r instanceof Xe)return new Xe(n.value);if(n instanceof Xe&&r instanceof tn){const t=r.type.now();if(t instanceof Ve){const e=n.value,s=t.to,i=t.type,a=r.neutral;return new tn(new Ve(i,e,s),new Ee(new ie(new Ve(i,e,e),new Xe(e)),a))}}else if(n instanceof tn&&r instanceof Xe){const t=n.type.now();if(t instanceof Ve){const e=t.from,s=r.value,i=t.type,a=n.neutral;return new tn(new Ve(i,e,s),new ve(a,new ie(new Ve(i,s,s),new Xe(s))))}}else if(n instanceof tn&&r instanceof tn){const t=n.type.now(),e=r.type.now();if(t instanceof Ve&&e instanceof Ve){const s=t.from,i=e.to,a=t.type,o=n.neutral,c=r.neutral;return new tn(new Ve(a,s,i),new Pe(o,c))}}throw new Error(`invalid input for do-trans: ${[t,e]}`)}(this.left.toLazy(t),this.right.toLazy(t))}prettyPrint(){return`(trans ${this.left.prettyPrint()} ${this.right.prettyPrint()})`}toString(){return this.prettyPrint()}},Mn=class extends on{target;base;fun;constructor(t,e,n){super(),this.target=t,this.base=e,this.fun=n}valOf(t){return function(t,e,n){const r=t.now();if(r instanceof Xe)return new Xe(Vt(n,r.value));if(r instanceof tn){const t=r.type.now();if(t instanceof Ve){const s=t.type,i=t.from,a=t.to,o=r.neutral;return new tn(new Ve(e,Vt(n,i),Vt(n,a)),new Te(o,new ie(new Ge("x",s,new kt(t=>e)),n)))}}throw new Error(`invalid input for cong 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Ye}prettyPrint(){return"vecnil"}toString(){return this.prettyPrint()}},Fn=class extends on{vec;constructor(t){super(),this.vec=t}valOf(t){return function(t){const e=t.now();if(e instanceof je)return e.head;if(e instanceof tn){const t=e.type.now();if(t instanceof Ke&&t.length.now()instanceof Me)return new tn(t.entryType,new xe(e.neutral))}throw new Error(`invalid input for head ${t}`)}(this.vec.toLazy(t))}prettyPrint(){return`(head ${this.vec.prettyPrint()})`}toString(){return this.prettyPrint()}},Qn=class extends on{vec;constructor(t){super(),this.vec=t}valOf(t){return te(this.vec.toLazy(t))}prettyPrint(){return`(tail ${this.vec.prettyPrint()})`}toString(){return this.prettyPrint()}},Vn=class extends on{length;target;motive;base;step;constructor(t,e,n,r,s){super(),this.length=t,this.target=e,this.motive=n,this.base=r,this.step=s}valOf(t){return ne(this.length.toLazy(t),this.target.toLazy(t),this.motive.toLazy(t),this.base.toLazy(t),this.step.toLazy(t))}prettyPrint(){return`ind-Vec 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Jn&&s instanceof Jn){const t=r.name,i=s.name;if($t(t)&&$t(i)){const r=rr(t,e),s=rr(i,n);return r!==er&&s!==er?r===s:r===er&&s===er&&t===i}return!1}return r instanceof En&&s instanceof En?r.sym===s.sym:r instanceof mn&&s instanceof mn||r instanceof Pn&&s instanceof Pn?sr(t,e,n,r.type,s.type)&&sr(t+1,nr(e,r.name,t),nr(n,s.name,t),r.body,s.body):r instanceof gn&&s instanceof gn?sr(t+1,nr(e,r.param,t),nr(n,s.param,t),r.body,s.body):r instanceof cn&&s instanceof cn&&r.type instanceof An&&s.type instanceof An||(r instanceof Wn&&s instanceof Wn?sr(t,e,n,r.fun,s.fun)&&sr(t,e,n,r.arg,s.arg):r instanceof un&&s instanceof un||r instanceof hn&&s instanceof hn||r instanceof ln&&s instanceof ln||r instanceof vn&&s instanceof vn||r instanceof An&&s instanceof An||r instanceof Ln&&s instanceof Ln||r instanceof _n&&s instanceof _n||r instanceof Dn&&s instanceof Dn||r instanceof On&&s instanceof On||(r instanceof cn&&s instanceof cn?sr(t,e,n,r.type,s.type)&&sr(t,e,n,r.expr,s.expr):r instanceof kn&&s instanceof kn?sr(t,e,n,r.elemType,s.elemType):r instanceof pn&&s instanceof pn?sr(t,e,n,r.n,s.n):r instanceof wn&&s instanceof wn||r instanceof fn&&s instanceof fn||r instanceof yn&&s instanceof yn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.step,s.step):r instanceof dn&&s instanceof dn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.step,s.step):r instanceof Tn&&s instanceof Tn?sr(t,e,n,r.first,s.first)&&sr(t,e,n,r.second,s.second):r instanceof bn&&s instanceof bn||r instanceof Nn&&s instanceof Nn?sr(t,e,n,r.pair,s.pair):r instanceof xn&&s instanceof xn?sr(t,e,n,r.head,s.head)&&sr(t,e,n,r.tail,s.tail):r instanceof $n&&s instanceof $n?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.step,s.step):r instanceof Sn&&s instanceof Sn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.step,s.step):r instanceof In&&s instanceof In?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive):r instanceof Cn&&s instanceof Cn?sr(t,e,n,r.type,s.type)&&sr(t,e,n,r.left,s.left)&&sr(t,e,n,r.right,s.right):r instanceof Bn&&s instanceof Bn?sr(t,e,n,r.type,s.type):r instanceof Rn&&s instanceof Rn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.base,s.base):r instanceof qn&&s instanceof qn?sr(t,e,n,r.left,s.left)&&sr(t,e,n,r.right,s.right):r instanceof Mn&&s instanceof Mn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.fun,s.fun):r instanceof Gn&&s instanceof Gn?sr(t,e,n,r.equality,s.equality):r instanceof Un&&s instanceof Un?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.base,s.base):r instanceof Hn&&s instanceof Hn?sr(t,e,n,r.type,s.type)&&sr(t,e,n,r.length,s.length):r instanceof zn&&s instanceof zn?sr(t,e,n,r.head,s.head)&&sr(t,e,n,r.tail,s.tail):r instanceof Fn&&s instanceof Fn||r instanceof Qn&&s instanceof Qn?sr(t,e,n,r.vec,s.vec):r instanceof Vn&&s instanceof Vn?sr(t,e,n,r.length,s.length)&&sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.base,s.base)&&sr(t,e,n,r.step,s.step):r instanceof Xn&&s instanceof Xn?sr(t,e,n,r.left,s.left)&&sr(t,e,n,r.right,s.right):r instanceof Kn&&s instanceof Kn||r instanceof Yn&&s instanceof Yn?sr(t,e,n,r.value,s.value):r instanceof jn&&s instanceof jn?sr(t,e,n,r.target,s.target)&&sr(t,e,n,r.motive,s.motive)&&sr(t,e,n,r.baseLeft,s.baseLeft)&&sr(t,e,n,r.baseRight,s.baseRight):r instanceof Zn&&s instanceof Zn&&(function(t,e){return t.startLine===e.startLine&&t.startColumn===e.startColumn&&t.endLine===e.endLine&&t.endColumn===e.endColumn}(r.loc,s.loc)&&sr(t,e,n,r.type,s.type))))}function ir(t,e){t.forInfo}function ar(t,e){const n=t.get(e);return n||e}function or(t,e,n){return new Map([[e,n],...t])}function cr(t,e,n,r){const s=n.readBackType(t),i=r.readBackType(t);return tr(s,i)?new Pt(void 0):new Tt(e,new vt([`Expected ${i} but got ${s}`]))}function ur(t,e,n,r,s){return tr(se(t,n,r),se(t,n,s))?new Pt(void 0):new Tt(e,new vt([`The terms ${r.prettyPrint()} and ${s.prettyPrint()} are not the same ${n.prettyPrint()}.`]))}function hr(t){return lr(t.split(""))}function lr(t){return 0===t.length||(e=t[0],!(!/^[a-zA-Z]$/.test(e)&&"-"!==t[0])&&lr(t.slice(1)));var e}function pr(t,e,n){return new us(t.location,t,e,n)}class wr{static synthNat(t,e){return new Pt(new cn(new un,new hn))}static synthUniverse(t,e,n){return new Tt(n,new vt(["U is a type, but it does not have a type."]))}static synthArrow(t,e,n,r,s,i){if(0===i.length){const n=Lt(t,s,"x"),i=new bt("Aout"),a=new bt("Bout");return Nt([[i,()=>r.check(t,e,new en)],[a,()=>s.check(Qt(t,n,Ct(t,i.value)),e,new en)]],()=>new Pt(new cn(new un,new mn(n,i.value,a.value))))}{const[a,...o]=i,c=Lt(t,pr(s,a,o),"x"),u=new bt("Aout"),h=new bt("tout");return Nt([[u,()=>r.check(t,e,new en)],[h,()=>new Nr(ht(n),s,a,o).check(Qt(t,c,Ct(t,u.value)),e,new en)]],()=>new Pt(new cn(new un,new mn(c,u.value,h.value))))}}static synthPi(t,e,n,r,s){if(1===r.length){const[n,i]=[r[0].binder,r[0].type],a=Ot(t,n.varName),o=(n.location,new bt("Aout")),c=new bt("Bout");return Nt([[o,()=>i.check(t,e,new en)],[c,()=>s.check(Qt(t,a,Ct(t,o.value)),or(e,n.varName,a),new en)]],()=>(o.value,new Pt(new cn(new un,new mn(a,o.value,c.value)))))}if(r.length>1){const[i,...a]=r,[o,c]=[i.binder,i.type],u=(o.location,o.varName),h=Ot(t,u),l=new bt("Aout"),p=new bt("Bout");return Nt([[l,()=>c.check(t,e,new en)],[p,()=>new xr(ht(n),a,s).check(Qt(t,h,Ct(t,l.value)),or(e,u,h),new en)]],()=>(l.value,new Pt(new cn(new un,new mn(h,l.value,p.value)))))}throw new Error("Invalid number of binders in Pi type")}static synthZero(t,e){return new Pt(new cn(new hn,new ln))}static synthAdd1(t,e,n){const r=new bt("nout");return Nt([[r,()=>n.check(t,e,new Re)]],()=>new Pt(new cn(new hn,new pn(r.value))))}static synthWhichNat(t,e,n,r,s){const i=new bt("tgtout"),a=new bt("bout"),o=new bt("sout"),c=Ot(t,"n_minus_1");return Nt([[i,()=>n.check(t,e,new Re)],[a,()=>r.synth(t,e)],[o,()=>s.check(t,e,new Ge(c,new Re,new _t(Mt(t),c,a.value.type)))]],()=>new Pt(new cn(a.value.type,new wn(i.value,new cn(a.value.type,a.value.expr),o.value))))}static synthIterNat(t,e,n,r,s){const i=new bt("tgtout"),a=new bt("bout"),o=new bt("sout");return Nt([[i,()=>n.check(t,e,new Re)],[a,()=>r.synth(t,e)],[o,()=>s.check(t,e,(()=>{const e=Ot(t,"old");return Ct(t,new mn(e,a.value.type,a.value.type))})())]],()=>new Pt(new cn(a.value.type,new fn(i.value,new cn(a.value.type,a.value.expr),o.value))))}static synthRecNat(t,e,n,r,s){const i=new bt("tgtout"),a=new bt("bout"),o=new bt("sout");return Nt([[i,()=>n.check(t,e,new Re)],[a,()=>r.synth(t,e)],[o,()=>s.check(t,e,(()=>{const e=Ot(t,"n_minus_1"),n=Ot(t,"old");return Ct(t,new mn(e,new hn,new mn(n,a.value.type,a.value.type)))})())]],()=>new Pt(new cn(a.value.type,new yn(i.value,new cn(a.value.type,a.value.expr),o.value))))}static synthIndNat(t,e,n,r,s,i){const a=new bt("tgtout"),o=new bt("motout"),c=new bt("motval"),u=new bt("bout"),h=new bt("sout");return Nt([[a,()=>n.check(t,e,new Re)],[o,()=>r.check(t,e,new Ge("n",new Re,new kt(t=>new en)))],[c,()=>new Pt(Ct(t,o.value))],[u,()=>s.check(t,e,Vt(c.value,new qe))],[h,()=>i.check(t,e,new Ge("n-1",new Re,new kt(t=>new Ge("x",Vt(c.value,t),new kt(e=>Vt(c.value,new Me(t)))))))]],()=>new Pt(new cn(new Wn(o.value,a.value),new dn(a.value,o.value,u.value,h.value))))}static synthAtom(t,e){return new Pt(new cn(new un,new vn))}static synthPair(t,e,n,r){const s=Ot(t,"a"),i=new bt("Aout"),a=new bt("Dout");return Nt([[i,()=>n.check(t,e,new en)],[a,()=>r.check(Qt(t,s,Ct(t,i.value)),e,new en)]],()=>new Pt(new cn(new un,new Pn(s,i.value,a.value))))}static synthSigma(t,e,n,r,s){if(1===r.length){const[n,i]=[r[0].binder,r[0].type],a=Ot(t,n.varName),o=(n.location,new bt("Aout")),c=new bt("Dout");return Nt([[o,()=>i.check(t,e,new en)],[c,()=>s.check(Qt(t,a,Ct(t,o.value)),or(e,n.varName,a),new en)]],()=>(o.value,new Pt(new cn(new un,new Pn(a,o.value,c.value)))))}if(r.length>1){const[i,...a]=r,[o,c]=[i.binder,i.type],u=(o.location,o.varName),h=Ot(t,u),l=new bt("Aout"),p=new bt("Dout");return Nt([[l,()=>c.check(t,e,new en)],[p,()=>new kr(ht(n),a,s).check(Qt(t,h,Ct(t,l.value)),or(e,u,h),new en)]],()=>(l.value,new Pt(new cn(new un,new Pn(h,l.value,p.value)))))}throw new Error("Invalid number of binders in Sigma type")}static synthCar(t,e,n,r){const s=new bt("p_rst");return Nt([[s,()=>r.synth(t,e)]],()=>{const e=Ct(t,s.value.type);return e instanceof He?new Pt(new cn(e.carType.readBackType(t),new bn(s.value.expr))):new Tt(n,new vt([`car requires a Pair type, but was used as a: ${e}.`]))})}static synthCdr(t,e,n,r){const s=new bt("pout");return Nt([[s,()=>r.synth(t,e)]],()=>{const e=Ct(t,s.value.type);if(e instanceof He){const[n,r,i]=[e.carName,e.carType,e.cdrType];return new Pt(new cn(i.valOfClosure(jt(Ct(t,s.value.expr))).readBackType(t),new Nn(s.value.expr)))}return new Tt(n,new vt([`cdr requires a Pair type, but was used as a: ${e}.`]))})}static synthQuote(t,e,n,r){return hr(r)?new Pt(new cn(new vn,new En(r))):new Tt(n,new vt([`Invalid atom: ${r}. Atoms consist of letters and hyphens.`]))}static synthTrivial(t,e){return new Pt(new cn(new un,new On))}static synthSole(t,e){return new Pt(new cn(new On,new Ln))}static synthIndList(t,e,n,r,s,i,a){const o=new bt("tgtout"),c=new bt("motout"),u=new bt("motval"),h=new bt("bout"),l=new bt("sout");return Nt([[o,()=>r.synth(t,e)]],()=>{const[r,p]=[o.value.type,o.value.expr],w=Ct(t,r);if(w instanceof De){const n=w.entryType;return Nt([[c,()=>s.check(t,e,new Ge("xs",new De(n),new _t(Mt(t),"xs",new un)))],[u,()=>new Pt(Ct(t,c.value))],[h,()=>i.check(t,e,Vt(u.value,new Fe))],[l,()=>a.check(t,e,new Ge("e",n,new kt(t=>new Ge("es",new De(n),new kt(e=>new Ge("ih",Vt(u.value,e),new kt(n=>Vt(u.value,new Qe(t,e)))))))))]],()=>new Pt(new cn(new Wn(c.value,p),new Sn(p,c.value,h.value,l.value))))}return new Tt(n,new vt([`Not a List: ${w.readBackType(t)}.`]))})}static synthRecList(t,e,n,r,s,i){const a=new bt("tgtout");return Nt([[a,()=>r.synth(t,e)]],()=>{const[r,o]=[a.value.type,a.value.expr],c=Ct(t,r);if(c instanceof De){const n=c.entryType,r=new bt("bout"),a=new bt("btval"),u=new bt("sout");return Nt([[r,()=>s.synth(t,e)],[a,()=>new Pt(Ct(t,r.value.type))],[u,()=>i.check(t,e,new Ge("e",n,new kt(t=>new Ge("es",new De(n),new kt(t=>new Ge("ih",a.value,new kt(t=>a.value)))))))]],()=>new Pt(new cn(r.value.type,new $n(o,new cn(r.value.type,r.value.expr),u.value))))}return new Tt(n,new vt([`Not a List: ${c.readBackType(t)}.`]))})}static synthList(t,e,n){const r=new bt("Eout");return Nt([[r,()=>n.entryType.check(t,e,new en)]],()=>new Pt(new cn(new un,new kn(r.value))))}static synthListCons(t,e,n,r){const s=new bt("eout"),i=new bt("esout");return Nt([[s,()=>n.synth(t,e)],[i,()=>r.check(t,e,Ct(t,new kn(s.value.type)))]],()=>new Pt(new cn(new kn(s.value.type),new xn(s.value.expr,i.value))))}static synthAbsurd(t,e,n){return new Pt(new cn(new un,new An))}static synthIndAbsurd(t,e,n){const r=new bt("tgtout"),s=new bt("motout");return Nt([[r,()=>n.target.check(t,e,new an)],[s,()=>n.motive.check(t,e,new en)]],()=>new Pt(new cn(s.value,new In(r.value,s.value))))}static synthEqual(t,e,n,r,s){const i=new bt("Aout"),a=new bt("Av"),o=new bt("from_out"),c=new bt("to_out");return Nt([[i,()=>n.check(t,e,new en)],[a,()=>new Pt(Ct(t,i.value))],[o,()=>r.check(t,e,a.value)],[c,()=>s.check(t,e,a.value)]],()=>new Pt(new cn(new un,new Cn(i.value,o.value,c.value))))}static synthReplace(t,e,n,r,s,i){const a=new bt("tgt_rst"),o=new bt("motout"),c=new bt("bout");return Nt([[a,()=>r.synth(t,e)]],()=>{const r=Ct(t,a.value.type);if(r instanceof Ve){const[n,u,h]=[r.type,r.from,r.to];return Nt([[o,()=>s.check(t,e,new Ge("x",n,new kt(t=>new en)))],[c,()=>i.check(t,e,Vt(Ct(t,o.value),u))]],()=>new Pt(new cn(Vt(Ct(t,o.value),h).readBackType(t),new Rn(a.value.expr,o.value,c.value))))}return new Tt(n,new vt([`Expected an expression with = type, but the type was: ${a.value.type}.`]))})}static synthTrans(t,e,n,r,s){const i=new bt("p1_rst"),a=new bt("p2_rst");return Nt([[i,()=>r.synth(t,e)],[a,()=>s.synth(t,e)]],()=>{const e=Ct(t,i.value.type),r=Ct(t,a.value.type);if(e instanceof Ve&&r instanceof Ve){const[s,o,c]=[e.type,e.from,e.to],[u,h,l]=[r.type,r.from,r.to];return Nt([[new bt("_"),()=>cr(t,n,s,u)],[new bt("_"),()=>ur(t,n,s,c,h)]],()=>new Pt(new cn(new Ve(s,o,l).readBackType(t),new qn(i.value.expr,a.value.expr))))}return new Tt(n,new vt([`Expected =, got ${e} and ${r}.`]))})}static synthCong(t,e,n,r,s){const i=new bt("bout"),a=new bt("f_rst");return Nt([[i,()=>r.synth(t,e)],[a,()=>s.synth(t,e)]],()=>{const e=Ct(t,i.value.type),r=Ct(t,a.value.type);if(e instanceof Ve){const[s,o,c]=[e.type,e.from,e.to];if(r instanceof Ge){const[e,u,h]=[r.argName,r.argType,r.resultType],l=new bt("ph"),p=new bt("Cv"),w=new bt("fv");return Nt([[l,()=>cr(t,n,s,u)],[p,()=>new Pt(h.valOfClosure(o))],[w,()=>new Pt(Ct(t,a.value.expr))]],()=>new Pt(new cn(new Cn(p.value.readBackType(t),se(t,p.value,Vt(w.value,o)),se(t,p.value,Vt(w.value,c))),new Mn(i.value.expr,p.value.readBackType(t),a.value.expr))))}return new Tt(n,new vt([`Expected a function type, got ${r.readBackType(t)}.`]))}return new Tt(n,new vt([`Expected an = type, got ${e.readBackType(t)}.`]))})}static synthSymm(t,e,n,r){const s=new bt("eout");return Nt([[s,()=>r.synth(t,e)]],()=>{const e=Ct(t,s.value.type);if(e instanceof Ve){const[n,r,i]=[e.type,e.from,e.to];return new Pt(new cn(new Ve(n,i,r).readBackType(t),new Gn(s.value.expr)))}return new Tt(n,new vt([`Expected an = type, got ${e.readBackType(t)}.`]))})}static synthIndEqual(t,e,n,r,s,i){const a=new bt("tgtout"),o=new bt("motout"),c=new bt("motv"),u=new bt("baseout");return Nt([[a,()=>r.synth(t,e)]],()=>{const r=Ct(t,a.value.type);if(r instanceof Ve){const[n,h,l]=[r.type,r.from,r.to];return Nt([[o,()=>s.check(t,e,new Ge("to",n,new kt(t=>new Ge("p",new Ve(n,h,t),new kt(t=>new en)))))],[c,()=>new Pt(Ct(t,o.value))],[u,()=>i.check(t,e,Vt(Vt(c.value,h),new Xe(h)))]],()=>new Pt(new cn(Vt(Vt(c.value,l),Ct(t,a.value.expr)).readBackType(t),new Un(a.value.expr,o.value,u.value))))}return new Tt(n,new vt([`Expected evidence of equality, got ${r.readBackType(t)}.`]))})}static synthVec(t,e,n,r){const s=new bt("tout"),i=new bt("lenout");return Nt([[s,()=>n.check(t,e,new en)],[i,()=>r.check(t,e,new Re)]],()=>new Pt(new cn(new un,new Hn(s.value,i.value))))}static synthHead(t,e,n,r){const s=new bt("vout");return Nt([[s,()=>r.synth(t,e)]],()=>{const e=Ct(t,s.value.type).now();if(e instanceof Ke){const[r,i]=[e.entryType,e.length];return i.now()instanceof Me?new Pt(new cn(r.readBackType(t),new Fn(s.value.expr))):new Tt(n,new vt([`Expected a Vec with add1 at the top of the length, got ${se(t,new Re,i)}.`]))}return new Tt(n,new vt([`Expected a Vec, got ${e.readBackType(t)}.`]))})}static synthTail(t,e,n,r){const s=new bt("vout");return Nt([[s,()=>r.synth(t,e)]],()=>{const e=Ct(t,s.value.type).now();if(e instanceof Ke){const[r,i]=[e.entryType,e.length],a=i.now();if(a instanceof Me){const e=a.smaller;return new Pt(new cn(new Hn(r.readBackType(t),se(t,new Re,e)),new Qn(s.value.expr)))}return new Tt(n,new vt([`Expected a Vec with add1 at the top of the length, got ${se(t,new Re,i)}.`]))}return new Tt(n,new vt([`Expected a Vec, got ${e.readBackType(t)}.`]))})}static synthIndVec(t,e,n,r,s,i,a,o){const c=new bt("lenout"),u=new bt("lenv"),h=new bt("vecout"),l=new bt("motout"),p=new bt("motval"),w=new bt("bout"),f=new bt("sout");return Nt([[c,()=>r.check(t,e,new Re)],[u,()=>new Pt(Ct(t,c.value))],[h,()=>s.synth(t,e)]],()=>{const r=Ct(t,h.value.type);if(r instanceof Ke){const[s,y]=[r.entryType,r.length];return Nt([[new bt("_"),()=>ur(t,n,new Re,u.value,y)],[l,()=>i.check(t,e,new Ge("k",new Re,new kt(t=>new Ge("es",new Ke(s,t),new kt(t=>new en)))))],[p,()=>new Pt(Ct(t,l.value))],[w,()=>a.check(t,e,Vt(Vt(p.value,new qe),new Ye))],[f,()=>o.check(t,e,ee(s,p.value))]],()=>new Pt(new cn(new Wn(new Wn(l.value,c.value),h.value.expr),new Vn(c.value,h.value.expr,l.value,w.value,f.value))))}return new Tt(n,new vt([`Expected a Vec, got ${r.readBackType(t)}.`]))})}static synthEither(t,e,n,r){const s=new bt("Lout"),i=new bt("Rout");return Nt([[s,()=>n.check(t,e,new en)],[i,()=>r.check(t,e,new en)]],()=>new Pt(new cn(new un,new Xn(s.value,i.value))))}static synthIndEither(t,e,n,r,s,i,a){const o=new bt("tgtout"),c=new bt("motout"),u=new bt("motval"),h=new bt("lout"),l=new bt("rout");return Nt([[o,()=>r.synth(t,e)]],()=>{const r=Ct(t,o.value.type);if(r instanceof Ze){const[n,p]=[r.leftType,r.rightType];return Nt([[c,()=>s.check(t,e,new Ge("x",new Ze(n,p),new kt(t=>new en)))],[u,()=>new Pt(Ct(t,c.value))],[h,()=>i.check(t,e,new Ge("x",n,new kt(t=>Vt(u.value,new We(t)))))],[l,()=>a.check(t,e,new Ge("x",p,new kt(t=>Vt(u.value,new Je(t)))))]],()=>new Pt(new cn(new Wn(c.value,o.value.expr),new jn(o.value.expr,c.value,h.value,l.value))))}return new Tt(n,new vt([`Expected an Either, but got a ${r.readBackType(t)}.`]))})}static synthThe(t,e,n,r){const s=new bt("t_out"),i=new bt("e_out");return Nt([[s,()=>n.isType(t,e)],[i,()=>r.check(t,e,Ct(t,s.value))]],()=>new Pt(new cn(s.value,i.value)))}static synthApplication(t,e,n,r,s,i){if(0===i.length){const i=new bt("fout");return Nt([[i,()=>r.synth(t,e)]],()=>{const r=Ct(t,i.value.type);if(r instanceof Ge){const[n,a,o]=[r.argName,r.argType,r.resultType],c=new bt("argout");return Nt([[c,()=>s.check(t,e,a)]],()=>new Pt(new cn(o.valOfClosure(Ct(t,c.value)).readBackType(t),new Wn(i.value.expr,c.value))))}return new Tt(n,new vt([`Not a function type: ${r.readBackType(t)}.`]))})}{const a=new bt("appout");return Nt([[a,()=>new us(ht(n),r,s,i.slice(0,i.length-1)).synth(t,e)]],()=>{const r=Ct(t,a.value.type);if(r instanceof Ge){const[n,s,o]=[r.argName,r.argType,r.resultType],c=new bt("fout");return Nt([[c,()=>i[i.length-1].check(t,e,s)]],()=>new Pt(new cn(o.valOfClosure(Ct(t,c.value)).readBackType(t),new Wn(a.value.expr,c.value))))}return new Tt(n,new vt([`Not a function type: ${r.readBackType(t)}.`]))})}}static synthName(t,e,n,r){const s=ar(e,r),i=new bt("x_tv");return Nt([[i,()=>Ft(t,0,s)]],()=>(t.get(s),new Pt(new cn(i.value.readBackType(t),new Jn(s)))))}static synthNumber(t,e,n,r){if(0===r)return new Pt(new cn(new hn,new ln));if(r>0){const s=new bt("n_1_out");return Nt([[s,()=>new Mr(n,r-1).check(t,e,new Re)]],()=>new Pt(new cn(new hn,new pn(s.value))))}return new Tt(n,new vt([`Expected a positive number, got ${r}.`]))}}class fr{location;constructor(t){this.location=t}isType(t,e){const n=new bt("ok"),r=this.getType(t,e);return Nt([[n,()=>r]],()=>(ir(this.location,n.value),new Pt(n.value)))}getType(t,e){const n=this.check(t,e,new en);if(n instanceof Pt)return n;if(n instanceof Tt){if(this instanceof $r&&$t(this.name)){const e=new bt("other-tv");return new Nt([[e,()=>Ft(t,this.location,this.name)]],()=>{new Tt(this.location,new vt([`Expected U, but given ${e.value.readBackType(t)}`]))})}return new Tt(this.location,new vt(["not a type"]))}throw new Error("Invalid checkType")}check(t,e,n){const r=new bt("ok"),s=this.checkOut(t,e,n);return Nt([[r,()=>s]],()=>new Pt(r.value))}synth(t,e){const n=new bt("ok");return Nt([[n,()=>this.synthHelper(t,e)]],()=>(ir(this.location,n.value.type),new Pt(n.value)))}checkOut(t,e,n){const r=new bt("theT");return Nt([[r,()=>this.synth(t,e)],[new bt("_"),()=>cr(t,this.location,Ct(t,r.value.type),n)]],()=>new Pt(r.value.expr))}}class yr extends fr{location;type;value;constructor(t,e,n){super(t),this.location=t,this.type=e,this.value=n}synthHelper(t,e){return wr.synthThe(t,e,this.type,this.value)}findNames(){return this.type.findNames().concat(this.value.findNames())}prettyPrint(){return`(the ${this.type.prettyPrint()} ${this.value.prettyPrint()})`}toString(){return this.prettyPrint()}}class dr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthUniverse(t,e,this.location)}findNames(){return[]}getType(t,e){return new Pt(new un)}prettyPrint(){return"U"}toString(){return this.prettyPrint()}}class mr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthNat(t,e)}findNames(){return[]}getType(t,e){return new Pt(new hn)}prettyPrint(){return"Nat"}toString(){return this.prettyPrint()}}class gr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthZero(t,e)}findNames(){return[]}prettyPrint(){return"zero"}toString(){return this.prettyPrint()}}class vr extends fr{location;base;constructor(t,e){super(t),this.location=t,this.base=e}synthHelper(t,e){return wr.synthAdd1(t,e,this.base)}findNames(){return this.base.findNames()}prettyPrint(){return`(add1 ${this.base.prettyPrint()})`}toString(){return this.prettyPrint()}}class Er extends fr{location;target;base;step;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.base=n,this.step=r}synthHelper(t,e){return wr.synthWhichNat(t,e,this.target,this.base,this.step)}findNames(){return this.target.findNames().concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(which-nat ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class Pr extends fr{location;target;base;step;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.base=n,this.step=r}synthHelper(t,e){return wr.synthIterNat(t,e,this.target,this.base,this.step)}findNames(){return this.target.findNames().concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(iter-nat ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class Tr extends fr{location;target;base;step;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.base=n,this.step=r}synthHelper(t,e){return wr.synthRecNat(t,e,this.target,this.base,this.step)}findNames(){return this.target.findNames().concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(rec-nat ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class br extends fr{location;target;motive;base;step;constructor(t,e,n,r,s){super(t),this.location=t,this.target=e,this.motive=n,this.base=r,this.step=s}synthHelper(t,e){return wr.synthIndNat(t,e,this.target,this.motive,this.base,this.step)}findNames(){return this.target.findNames().concat(this.motive.findNames()).concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(ind-nat ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class Nr extends fr{location;arg1;arg2;args;constructor(t,e,n,r){super(t),this.location=t,this.arg1=e,this.arg2=n,this.args=r}synthHelper(t,e){return wr.synthArrow(t,e,this.location,this.arg1,this.arg2,this.args)}findNames(){return this.arg1.findNames().concat(this.arg2.findNames()).concat(this.args.flatMap(t=>t.findNames()))}getType(t,e){const[n,r,s]=[this.arg1,this.arg2,this.args];if(0===s.length){const s=Lt(t,r,"x"),i=new bt("Aout"),a=new bt("Bout");return Nt([[i,()=>n.isType(t,e)],[a,()=>r.isType(Qt(t,s,Ct(t,i.value)),e)]],()=>new Pt(new mn(s,i.value,a.value)))}{const[i,...a]=s,o=Lt(t,pr(r,i,a),"x"),c=new bt("Aout"),u=new bt("tout");return Nt([[c,()=>n.isType(t,e)],[u,()=>new Nr(ht(this.location),r,i,a).isType(Qt(t,o,Ct(t,c.value)),e)]],()=>new Pt(new mn(o,c.value,u.value)))}}prettyPrint(){return`(-> ${this.arg1.prettyPrint()} ${this.arg2.prettyPrint()} ${this.args.map(t=>t.prettyPrint()).join(" ")})`}toString(){return this.prettyPrint()}}class xr extends fr{location;binders;body;constructor(t,e,n){super(t),this.location=t,this.binders=e,this.body=n}synthHelper(t,e){return wr.synthPi(t,e,this.location,this.binders,this.body)}findNames(){return this.binders.flatMap(t=>At(t)).concat(this.body.findNames())}getType(t,e){const[n,r]=[this.binders,this.body];if(1===n.length){const[s,i]=[n[0].binder,n[0].type],a=Ot(t,s.varName),o=(s.location,new bt("Aout")),c=new bt("Aoutv"),u=new bt("Bout");return Nt([[o,()=>i.isType(t,e)],[c,()=>new Pt(Ct(t,o.value))],[u,()=>r.isType(Qt(t,a,c.value),or(e,s.varName,a))]],()=>(o.value,new Pt(new mn(a,o.value,u.value))))}if(n.length>1){const[s,...i]=n,[a,o]=[s.binder.varName,s.type],c=Ot(t,a),u=(s.binder.location,new bt("Aout")),h=new bt("Aoutv"),l=new bt("Bout");return Nt([[u,()=>o.isType(t,e)],[h,()=>new Pt(Ct(t,u.value))],[l,()=>new xr(ht(this.location),i,r).isType(Qt(t,c,h.value),or(e,s.binder.varName,c))]],()=>(u.value,new Pt(new mn(c,u.value,l.value))))}throw new Error("Invalid number of binders in Pi type")}prettyPrint(){return`(Π ${this.binders.map(t=>`(${t.binder.varName} ${t.type.prettyPrint()})`).join(" ")} \n            ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}}class _r extends fr{location;binders;body;constructor(t,e,n){super(t),this.location=t,this.binders=e,this.body=n}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return this.binders.map(t=>t.varName).concat(this.body.findNames())}checkOut(t,e,n){if(1===this.binders.length){const r=this.body,s=this.binders[0],i=s.varName,a=s.location,o=n.now();if(o instanceof Ge){const n=o.argType,s=o.resultType,a=ar(e,i),c=new bt("bout");return Nt([[c,()=>r.check(Qt(t,a,n),or(e,i,a),s.valOfClosure(new tn(n,new oe(a))))]],()=>(n.readBackType(t),new Pt(new gn(a,c.value))))}return new Tt(a,new vt([`Not a function type: ${o.readBackType(t)}.`]))}return new _r(this.location,[this.binders[0]],new _r(ht(this.location),this.binders.slice(1),this.body)).check(t,e,n)}prettyPrint(){return`(lambda ${this.binders.map(t=>t.varName).join(" ")} ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}}class kr extends fr{location;binders;body;constructor(t,e,n){super(t),this.location=t,this.binders=e,this.body=n}synthHelper(t,e){return wr.synthSigma(t,e,this.location,this.binders,this.body)}findNames(){return this.binders.flatMap(t=>At(t)).concat(this.body.findNames())}getType(t,e){const[n,r]=[this.binders,this.body];if(1===n.length){const[s,i]=[n[0].binder,n[0].type],a=s.varName,o=Ot(t,a),c=(s.location,new bt("Aout")),u=new bt("Aoutv"),h=new bt("Dout");return Nt([[c,()=>i.isType(t,e)],[u,()=>new Pt(Ct(t,c.value))],[h,()=>r.isType(Qt(t,o,u.value),or(e,a,o))]],()=>(c.value,new Pt(new Pn(o,c.value,h.value))))}if(n.length>1){const[[s,i],...a]=[[n[0].binder,n[0].type],n[1],...n.slice(2)],o=s.varName,c=Ot(t,o),u=(s.location,new bt("Aout")),h=new bt("Aoutv"),l=new bt("Dout");return Nt([[u,()=>i.isType(t,e)],[h,()=>new Pt(Ct(t,u.value))],[l,()=>new kr(this.location,a,r).isType(Qt(t,o,h.value),or(e,o,c))]],()=>(u.value,new Pt(new Pn(c,u.value,l.value))))}throw new Error("Invalid number of binders in Sigma type")}prettyPrint(){return`(Σ ${this.binders.map(t=>`(${t.binder.varName} ${t.type.prettyPrint()})`).join(" ")} \n            ${this.body.prettyPrint()})`}toString(){return this.prettyPrint()}}class $r extends fr{location;name;constructor(t,e){super(t),this.location=t,this.name=e}synthHelper(t,e){return wr.synthName(t,e,this.location,this.name)}findNames(){return[this.name]}prettyPrint(){return this.name}toString(){return this.prettyPrint()}}class Sr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthAtom(t,e)}findNames(){return[]}getType(t,e){return new Pt(new vn)}prettyPrint(){return"Atom"}toString(){return this.prettyPrint()}}class Or extends fr{location;name;constructor(t,e){super(t),this.location=t,this.name=e}synthHelper(t,e){return wr.synthQuote(t,e,this.location,this.name)}findNames(){return[]}prettyPrint(){return`'${this.name}`}toString(){return this.prettyPrint()}}class Lr extends fr{location;first;second;constructor(t,e,n){super(t),this.location=t,this.first=e,this.second=n}synthHelper(t,e){return wr.synthPair(t,e,this.first,this.second)}findNames(){return this.first.findNames().concat(this.second.findNames())}getType(t,e){const n=new bt("Aout"),r=new bt("Dout"),s=Lt(t,this.second,"x");return Nt([[n,()=>this.first.isType(t,e)],[r,()=>this.second.isType(Qt(t,s,Ct(t,n.value)),e)]],()=>new Pt(new Pn(s,n.value,r.value)))}prettyPrint(){return`(Pair ${this.first.prettyPrint()} ${this.second.prettyPrint()})`}toString(){return this.prettyPrint()}}class Ar extends fr{location;first;second;constructor(t,e,n){super(t),this.location=t,this.first=e,this.second=n}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return this.first.findNames().concat(this.second.findNames())}checkOut(t,e,n){const r=n.now();if(r instanceof He){const n=r.carType,s=r.cdrType,i=new bt("aout"),a=new bt("dout");return Nt([[i,()=>this.first.check(t,e,n)],[a,()=>this.second.check(t,e,s.valOfClosure(Ct(t,i.value)))]],()=>new Pt(new Tn(i.value,a.value)))}return new Tt(this.location,new vt([`cons requires a Pair or Σ type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return`(cons ${this.first.prettyPrint()} ${this.second.prettyPrint()})`}toString(){return this.prettyPrint()}}class Ir extends fr{location;pair;constructor(t,e){super(t),this.location=t,this.pair=e}synthHelper(t,e){return wr.synthCar(t,e,this.location,this.pair)}findNames(){return this.pair.findNames()}prettyPrint(){return`(car ${this.pair.prettyPrint()})`}toString(){return this.prettyPrint()}}class Cr extends fr{location;pair;constructor(t,e){super(t),this.location=t,this.pair=e}synthHelper(t,e){return wr.synthCdr(t,e,this.location,this.pair)}findNames(){return this.pair.findNames()}prettyPrint(){return`(cdr ${this.pair.prettyPrint()})`}toString(){return this.prettyPrint()}}class Br extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthTrivial(t,e)}findNames(){return[]}getType(t,e){return new Pt(new On)}prettyPrint(){return"Trivial"}toString(){return this.prettyPrint()}}class Rr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthSole(t,e)}findNames(){return[]}prettyPrint(){return"Sole"}}class qr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return[]}checkOut(t,e,n){const r=n.now();return r instanceof De?new Pt(new _n):new Tt(this.location,new vt([`nil requires a List type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return"nil"}toString(){return this.prettyPrint()}}let Mr=class extends fr{location;value;constructor(t,e){super(t),this.location=t,this.value=e}synthHelper(t,e){return wr.synthNumber(t,e,this.location,this.value)}findNames(){return[]}prettyPrint(){return`${this.value}`}toString(){return this.prettyPrint()}};class Gr extends fr{location;entryType;constructor(t,e){super(t),this.location=t,this.entryType=e}synthHelper(t,e){return wr.synthList(t,e,this)}findNames(){return this.entryType.findNames()}getType(t,e){const n=new bt("Eout");return Nt([[n,()=>this.entryType.isType(t,e)]],()=>new Pt(new kn(n.value)))}prettyPrint(){return`(List ${this.entryType.prettyPrint()})`}toString(){return this.prettyPrint()}}class Ur extends fr{location;x;xs;constructor(t,e,n){super(t),this.location=t,this.x=e,this.xs=n}synthHelper(t,e){return wr.synthListCons(t,e,this.x,this.xs)}findNames(){return this.x.findNames().concat(this.xs.findNames())}prettyPrint(){return`(:: ${this.x.prettyPrint()} ${this.xs.prettyPrint()})`}toString(){return this.prettyPrint()}}class Hr extends fr{location;target;base;step;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.base=n,this.step=r}synthHelper(t,e){return wr.synthRecList(t,e,this.location,this.target,this.base,this.step)}findNames(){return this.target.findNames().concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(rec-list ${this.target.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class zr extends fr{location;target;motive;base;step;constructor(t,e,n,r,s){super(t),this.location=t,this.target=e,this.motive=n,this.base=r,this.step=s}synthHelper(t,e){return wr.synthIndList(t,e,this.location,this.target,this.motive,this.base,this.step)}findNames(){return this.target.findNames().concat(this.motive.findNames()).concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`(ind-list ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()} \n              ${this.step.prettyPrint()})`}toString(){return this.prettyPrint()}}class Dr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){return wr.synthAbsurd(t,e,this)}findNames(){return[]}getType(t,e){return new Pt(new An)}prettyPrint(){return"Absurd"}toString(){return this.prettyPrint()}}class Fr extends fr{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}synthHelper(t,e){return wr.synthIndAbsurd(t,e,this)}findNames(){return this.target.findNames().concat(this.motive.findNames())}prettyPrint(){return`(ind-Absurd \n              ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()})`}toString(){return this.prettyPrint()}}class Qr extends fr{location;type;left;right;constructor(t,e,n,r){super(t),this.location=t,this.type=e,this.left=n,this.right=r}synthHelper(t,e){return wr.synthEqual(t,e,this.type,this.left,this.right)}findNames(){return this.type.findNames().concat(this.left.findNames()).concat(this.right.findNames())}getType(t,e){const[n,r,s]=[this.type,this.left,this.right],i=new bt("Aout"),a=new bt("Av"),o=new bt("from_out"),c=new bt("to_out");return Nt([[i,()=>n.isType(t,e)],[a,()=>new Pt(Ct(t,i.value))],[o,()=>r.check(t,e,a.value)],[c,()=>s.check(t,e,a.value)]],()=>new Pt(new Cn(i.value,o.value,c.value)))}prettyPrint(){return`(= ${this.type.prettyPrint()} \n              ${this.left.prettyPrint()} \n              ${this.right.prettyPrint()})`}toString(){return this.prettyPrint()}}class Vr extends fr{location;type;constructor(t,e){super(t),this.location=t,this.type=e}findNames(){return this.type.findNames()}synthHelper(t,e){throw new Error("Method not implemented.")}checkOut(t,e,n){const r=n.now();if(r instanceof Ve){const n=r.type,s=r.from,i=r.to,a=new bt("cout"),o=new bt("val");return Nt([[a,()=>this.type.check(t,e,n)],[o,()=>new Pt(Ct(t,a.value))],[new bt("_"),()=>ur(t,this.type.location,n,s,o.value)],[new bt("_"),()=>ur(t,this.type.location,n,i,o.value)]],()=>new Pt(new Bn(a.value)))}return new Tt(this.location,new vt([`same requires an Equal type, but encounter: ${r.readBackType(t)}.`]))}prettyPrint(){return`(same ${this.type.prettyPrint()})`}toString(){return this.prettyPrint()}}class Xr extends fr{location;target;motive;base;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.motive=n,this.base=r}synthHelper(t,e){return wr.synthReplace(t,e,this.location,this.target,this.motive,this.base)}findNames(){return this.target.findNames().concat(this.motive.findNames()).concat(this.base.findNames())}prettyPrint(){return`(replace ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()})`}toString(){return this.prettyPrint()}}class Kr extends fr{location;left;right;synthHelper(t,e){return wr.synthTrans(t,e,this.location,this.left,this.right)}constructor(t,e,n){super(t),this.location=t,this.left=e,this.right=n}findNames(){return this.left.findNames().concat(this.right.findNames())}prettyPrint(){return`(trans ${this.left.prettyPrint()} ${this.right.prettyPrint()})`}toString(){return this.prettyPrint()}}class Yr extends fr{location;target;fun;constructor(t,e,n){super(t),this.location=t,this.target=e,this.fun=n}synthHelper(t,e){return wr.synthCong(t,e,this.location,this.target,this.fun)}findNames(){return this.target.findNames().concat(this.fun.findNames())}prettyPrint(){return`(cong ${this.target.prettyPrint()} ${this.fun.prettyPrint()})`}toString(){return this.prettyPrint()}}class jr extends fr{location;equality;constructor(t,e){super(t),this.location=t,this.equality=e}synthHelper(t,e){return wr.synthSymm(t,e,this.location,this.equality)}findNames(){return this.equality.findNames()}prettyPrint(){return`(symm ${this.equality.prettyPrint()})`}toString(){return this.prettyPrint()}}class Zr extends fr{location;target;motive;base;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.motive=n,this.base=r}synthHelper(t,e){return wr.synthIndEqual(t,e,this.location,this.target,this.motive,this.base)}findNames(){return this.target.findNames().concat(this.motive.findNames()).concat(this.base.findNames())}prettyPrint(){return`(ind-= ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.base.prettyPrint()})`}toString(){return this.prettyPrint()}}class Wr extends fr{location;type;length;constructor(t,e,n){super(t),this.location=t,this.type=e,this.length=n}synthHelper(t,e){return wr.synthVec(t,e,this.type,this.length)}findNames(){return this.type.findNames().concat(this.length.findNames())}getType(t,e){const n=new bt("Eout"),r=new bt("lenout");return Nt([[n,()=>this.type.isType(t,e)],[r,()=>this.length.check(t,e,new Re)]],()=>new Pt(new Hn(n.value,r.value)))}prettyPrint(){return`(Vec ${this.type.prettyPrint()} ${this.length.prettyPrint()})`}toString(){return this.prettyPrint()}}class Jr extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return[]}checkOut(t,e,n){const r=n.now();if(r instanceof Ke){return r.length.now()instanceof qe?new Pt(new Dn):new Tt(this.location,new vt([`vecnil requires a Vec type with length ZERO, but was used as a: \n          ${se(t,new Re,r.length)}.`]))}return new Tt(this.location,new vt([`vecnil requires a Vec type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return"vecnil"}toString(){return this.prettyPrint()}}class ts extends fr{location;x;xs;constructor(t,e,n){super(t),this.location=t,this.x=e,this.xs=n}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return this.x.findNames().concat(this.xs.findNames())}checkOut(t,e,n){const r=n.now();if(r instanceof Ke){const n=r.length.now();if(n instanceof Me){const s=new bt("hout"),i=new bt("tout"),a=n.smaller;return Nt([[s,()=>this.x.check(t,e,r.entryType)],[i,()=>this.xs.check(t,e,new Ke(r.entryType,a))]],()=>new Pt(new zn(s.value,i.value)))}return new Tt(this.location,new vt([`vec:: requires a Vec type with length Add1, but was used with a: \n          ${se(t,new Re,r.length)}.`]))}return new Tt(this.location,new vt([`vec:: requires a Vec type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return`(vec:: ${this.x.prettyPrint()} ${this.xs.prettyPrint()})`}toString(){return this.prettyPrint()}}class es extends fr{location;vec;constructor(t,e){super(t),this.location=t,this.vec=e}synthHelper(t,e){return wr.synthHead(t,e,this.location,this.vec)}findNames(){return this.vec.findNames()}prettyPrint(){return`(head ${this.vec.prettyPrint()})`}toString(){return this.prettyPrint()}}class ns extends fr{location;vec;constructor(t,e){super(t),this.location=t,this.vec=e}synthHelper(t,e){return wr.synthTail(t,e,this.location,this.vec)}findNames(){return this.vec.findNames()}prettyPrint(){return`(tail ${this.vec.prettyPrint()})`}toString(){return this.prettyPrint()}}class rs extends fr{location;length;target;motive;base;step;constructor(t,e,n,r,s,i){super(t),this.location=t,this.length=e,this.target=n,this.motive=r,this.base=s,this.step=i}synthHelper(t,e){return wr.synthIndVec(t,e,this.location,this.length,this.target,this.motive,this.base,this.step)}findNames(){return this.length.findNames().concat(this.target.findNames()).concat(this.motive.findNames()).concat(this.base.findNames()).concat(this.step.findNames())}prettyPrint(){return`ind-Vec ${this.length.prettyPrint()}\n              ${this.target.prettyPrint()}\n              ${this.motive.prettyPrint()}\n              ${this.base.prettyPrint()}\n              ${this.step.prettyPrint()}`}toString(){return this.prettyPrint()}}class ss extends fr{location;left;right;constructor(t,e,n){super(t),this.location=t,this.left=e,this.right=n}synthHelper(t,e){return wr.synthEither(t,e,this.left,this.right)}findNames(){return this.left.findNames().concat(this.right.findNames())}getType(t,e){const n=new bt("Lout"),r=new bt("Rout");return Nt([[n,()=>this.left.isType(t,e)],[r,()=>this.right.isType(t,e)]],()=>new Pt(new Xn(n.value,r.value)))}prettyPrint(){return`(Either ${this.left.prettyPrint()} ${this.right.prettyPrint()})`}toString(){return this.prettyPrint()}}class is extends fr{location;value;constructor(t,e){super(t),this.location=t,this.value=e}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return this.value.findNames()}checkOut(t,e,n){const r=n.now();if(r instanceof Ze){const n=new bt("lout");return Nt([[n,()=>this.value.check(t,e,r.leftType)]],()=>new Pt(new Kn(n.value)))}return new Tt(this.location,new vt([`left requires an Either type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return`(left ${this.value.prettyPrint()})`}toString(){return this.prettyPrint()}}class as extends fr{location;value;constructor(t,e){super(t),this.location=t,this.value=e}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return this.value.findNames()}checkOut(t,e,n){const r=n.now();if(r instanceof Ze){const n=new bt("rout");return Nt([[n,()=>this.value.check(t,e,r.rightType)]],()=>new Pt(new Yn(n.value)))}return new Tt(this.location,new vt([`right requires an Either type, but was used as a: ${r.readBackType(t)}.`]))}prettyPrint(){return`(right ${this.value.prettyPrint()})`}toString(){return this.prettyPrint()}}class os extends fr{location;target;motive;baseLeft;baseRight;constructor(t,e,n,r,s){super(t),this.location=t,this.target=e,this.motive=n,this.baseLeft=r,this.baseRight=s}synthHelper(t,e){return wr.synthIndEither(t,e,this.location,this.target,this.motive,this.baseLeft,this.baseRight)}findNames(){return this.target.findNames().concat(this.motive.findNames()).concat(this.baseLeft.findNames()).concat(this.baseRight.findNames())}prettyPrint(){return`(ind-Either ${this.target.prettyPrint()} \n              ${this.motive.prettyPrint()} \n              ${this.baseLeft.prettyPrint()} \n              ${this.baseRight.prettyPrint()})`}toString(){return this.prettyPrint()}}class cs extends fr{location;constructor(t){super(t),this.location=t}synthHelper(t,e){throw new Error("Method not implemented.")}findNames(){return[]}checkOut(t,e,n){const r=n.readBackType(t);return ir(this.location,Bt(t)),new Pt(new Zn(this.location.locationToSrcLoc(),r))}prettyPrint(){return"TODO"}toString(){return this.prettyPrint()}}class us extends fr{location;func;arg;args;constructor(t,e,n,r){super(t),this.location=t,this.func=e,this.arg=n,this.args=r}synthHelper(t,e){return wr.synthApplication(t,e,this.location,this.func,this.arg,this.args)}findNames(){return this.func.findNames().concat(this.arg.findNames()).concat(this.args.flatMap(t=>t.findNames()))}prettyPrint(){return`(${this.func.prettyPrint()} ${this.arg.prettyPrint()} ${this.args.map(t=>t.prettyPrint()).join(" ")})`}toString(){return this.prettyPrint()}}class hs{id;type;context;renaming;term;constructor(t,e,n,r,s){this.id=t,this.type=e,this.context=n,this.renaming=r,this.term=s}clone(t={}){return new hs(t.id??this.id,t.type??this.type,t.context??new Map(this.context),t.renaming??new Map(this.renaming),t.term??this.term)}addHypothesis(t,e){const n=Ot(this.context,t);It(this.context,n,new Ht(e))}getVariableType(t){const e=this.context.get(t);return e?.type}prettyPrintWithContext(){const t=Array.from(this.context.entries()).map(([t,e])=>`${t} : ${e.type.readBackType(this.context).prettyPrint()}`).join("\n  "),e=this.type.readBackType(this.context).prettyPrint();return t?`Context:\n  ${t}\n────────────────\nGoal: ${e}`:`Goal: ${e}`}}class ls{goal;children=[];parent=null;isComplete=!1;childFocusIndex=-1;constructor(t){this.goal=t}addChildren(t){t.forEach(t=>{t.parent=this}),this.children=t}findById(t){if(this.goal.id===t)return this;for(const e of this.children){const n=e.findById(t);if(n)return n}return null}}class ps{location;goalTree;currentGoal;proofHistory=[];goalIdCounter=0;constructor(t,e){this.location=t,this.goalTree=e,this.currentGoal=this.goalTree}static initialize(t,e,n){const r=new hs("goal_0",e,new Map(t),new Map),s=new ps(n,new ls(r));return s.currentGoal=s.goalTree,s}generateGoalId(){return"goal_"+ ++this.goalIdCounter}isComplete(){return this.goalTree.isComplete}getCurrentGoal(){if(null===this.currentGoal)throw new Error("No current goal available.");return new Pt(this.currentGoal.goal)}visualizeTree(){return this.visualizeNode(this.goalTree,"",!0)}visualizeNode(t,e,n){let r=e+(n?"└── ":"├── ")+`${t.isComplete?"✓":t===this.currentGoal?"→":"○"} ${t.goal.id}`+"\n";const s=e+(n?"    ":"│   ");for(let e=0;e<t.children.length;e++){const n=e===t.children.length-1;r+=this.visualizeNode(t.children[e],s,n)}return r}addGoal(t){this.currentGoal.addChildren(t),this.currentGoal.childFocusIndex=0,this.currentGoal=t[0]}nextGoal(){if(null===this.currentGoal.parent)return!0;const t=this.currentGoal.parent,e=this.nextGoalAux(t);return null===e||(this.currentGoal=e,!1)}nextGoalAux(t){return-1===t.childFocusIndex||t.childFocusIndex>=t.children.length-1?(t.isComplete=!0,null===t.parent?null:this.nextGoalAux(t.parent)):(t.childFocusIndex+=1,t.children[t.childFocusIndex])}previousGoal(){if(null===this.currentGoal.parent)throw new Error("No previous goal available at the root level.");const t=this.PreviousGoalAux(this.currentGoal);if(null===t)throw new Error("No previous goal found.");this.currentGoal=t}PreviousGoalAux(t){if(0===t.childFocusIndex)return t;{let e=!1,n=t.children[t.childFocusIndex-1];for(;!e;){if(-1===n.childFocusINdex)return e=!0,n;n=n.children[n.childFocusIndex]}}}}class ws{location;constructor(t){this.location=t}}class fs extends ws{location;varName;constructor(t,e){super(t),this.location=t,this.varName=e}getName(){return"intro"}toString(){return`intro ${this.varName||""}`}apply(t){const e=t.currentGoal.goal,n=e.type;if(!(n instanceof Ge))return new Tt(t.location,new vt([`Cannot introduce a variable for non-function type: ${n.prettyPrint()}`]));const r=this.varName||n.argName||Ot(e.context,"x"),s=e.renaming;r!==n.argName&&or(s,n.argName,r);const i=It(e.context,r,new Dt(n.argType)),a=n.resultType.valOfClosure(new tn(n.argType,new oe(r))),o=new ls(new hs(t.generateGoalId(),a,i,s));return t.addGoal([o]),new Pt(t)}}class ys extends ws{location;term;constructor(t,e){super(t),this.location=t,this.term=e}toString(){return`exact ${this.term.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.type;console.log("goalType:",n.prettyPrint()),console.log("term:",this.term.prettyPrint());const r=this.term.check(e.context,e.renaming,n);return r instanceof Tt?r:(t.currentGoal.isComplete=!0,t.nextGoal(),new Pt(t))}}class ds extends ws{location;value;varName;constructor(t,e,n){super(t),this.location=t,this.value=e,this.varName=n}toString(){return`exists ${this.varName||""}`}apply(t){const e=t.getCurrentGoal().result,n=e.type;if(!(n instanceof He))return new Tt(t.location,new vt([`Cannot use exists on non-product type: ${n.prettyPrint()}`]));const r=this.varName||n.carName||Ot(e.context,"x"),s=e.renaming;r!==n.carName&&or(s,n.carName,r);const i=this.value.check(e.context,e.renaming,n.carType);if(i instanceof Tt)return i;const a=i.result.valOf(Mt(e.context)),o=It(e.context,r,new zt(n.carType,a)),c=n.cdrType.valOfClosure(a),u=new ls(new hs(t.generateGoalId(),c,o,s));return t.addGoal([u]),new Pt(t)}}class ms extends ws{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}toString(){return`elim-nat ${this.target} to prove ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof Re))return new Tt(t.location,new vt([`Cannot eliminate non-Nat type: ${r.prettyPrint()}`]));const s=Ot(e.context,"n"),i=this.motive.check(e.context,e.renaming,new Ge(s,new Re,new kt(t=>new en)));if(i instanceof Tt)return i;{const n=this.eliminateNat(e.context,e.renaming,i.result.valOf(Mt(e.context)));return t.addGoal(n.map(n=>new ls(new hs(t.generateGoalId(),n,e.context,e.renaming)))),new Pt(t)}}eliminateNat(t,e,n){return[Vt(n,new qe),new Ge(Ot(t,"n-1"),new Re,new kt(e=>new Ge(Ot(t,"ih"),Vt(n,e),new kt(t=>Vt(n,new Me(e))))))]}}class gs extends ws{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}toString(){return`elim-list ${this.target} to prove ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof De))return new Tt(t.location,new vt([`Cannot eliminate non-List type: ${r.prettyPrint()}`]));Ot(e.context,"motive");const s=r.entryType,i=this.motive.check(e.context,e.renaming,new Ge("xs",new De(s),new _t(Mt(e.context),"xs",new un)));if(i instanceof Tt)return i;{const n=i.result.valOf(Mt(e.context)),r=this.eliminateList(e.context,e.renaming,n,s);return console.log("Eliminating List with motive"),t.addGoal(r.map(n=>new ls(new hs(t.generateGoalId(),n,e.context,e.renaming)))),new Pt(t)}}eliminateList(t,e,n,r){return[Vt(n,new Fe),new Ge(Ot(t,"x"),r,new kt(e=>new Ge(Ot(t,"xs"),new De(r),new kt(r=>new Ge(Ot(t,"ih"),Vt(n,r),new kt(t=>Vt(n,new Qe(e,r))))))))]}}class vs extends ws{location;target;motive;length;constructor(t,e,n,r){super(t),this.location=t,this.target=e,this.motive=n,this.length=r}toString(){return`elim-list ${this.target} to prove ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof Ke))return new Tt(t.location,new vt([`Cannot eliminate non-Vec type: ${r.prettyPrint()}`]));const s=this.length.check(e.context,e.renaming,new Re);if(s instanceof Tt)return s;const[i,a]=[r.entryType,r.length];ur(e.context,this.location,new Re,Ct(e.context,s.result),a),Ot(e.context,"motive");const o=this.motive.check(e.context,e.renaming,new Ge("k",new Re,new kt(t=>new Ge("es",new Ke(i,t),new kt(t=>new en)))));if(o instanceof Tt)return o;{const n=o.result.valOf(Mt(e.context)),r=this.eliminateVec(e.context,e.renaming,n,i);return t.addGoal(r.map(n=>new ls(new hs(t.generateGoalId(),n,e.context,e.renaming)))),new Pt(t)}}eliminateVec(t,e,n,r){return[Vt(Vt(n,new qe),new Ye),ee(r,n)]}}class Es extends ws{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}toString(){return`elim-equal ${this.target} with motive ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof Ve))return new Tt(t.location,new vt([`Cannot eliminate non-Equal type: ${r.prettyPrint()}`]));const[s,i,a]=[r.type,r.from,r.to],o=this.motive.check(e.context,e.renaming,new Ge("to",s,new kt(t=>new Ge("p",new Ve(s,i,t),new kt(t=>new en)))));if(o instanceof Tt)return o;{const n=[Vt(Vt(o.result.valOf(Mt(e.context)),i),new Xe(i))];return t.addGoal(n.map(n=>new ls(new hs(t.generateGoalId(),n,e.context,e.renaming)))),new Pt(t)}}}class Ps extends ws{location;constructor(t){super(t),this.location=t}toString(){return"left"}apply(t){const e=t.getCurrentGoal().result;if(!(e.type.now()instanceof Ze))return new Tt(t.location,new vt([`"left" expected goal type to be Either, but got: ${e.type.prettyPrint()}`]));const n=e.type.leftType.now();return t.addGoal([new ls(new hs(t.generateGoalId(),n,e.context,e.renaming))]),new Pt(t)}}class Ts extends ws{location;constructor(t){super(t),this.location=t}toString(){return"right"}apply(t){const e=t.getCurrentGoal().result;if(!(e.type.now()instanceof Ze))return new Tt(t.location,new vt([`"right" expected goal type to be Either, but got: ${e.type.prettyPrint()}`]));const n=e.type.rightType.now();return t.addGoal([new ls(new hs(t.generateGoalId(),n,e.context,e.renaming))]),new Pt(t)}}class bs extends ws{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}toString(){return`elim-either ${this.target} with motive ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof Ze))return new Tt(t.location,new vt([`Cannot eliminate non-Either type: ${r.prettyPrint()}`]));const[s,i]=[r.leftType,r.rightType],a=this.motive.check(e.context,e.renaming,new Ge("x",new Ze(s,i),new kt(t=>new en)));if(a instanceof Tt)return a;{const n=a.result.valOf(Mt(e.context)),r=new Ge("x",s,new kt(t=>Vt(n,new We(t)))),o=new Ge("x",i,new kt(t=>Vt(n,new Je(t))));return t.addGoal([new ls(new hs(t.generateGoalId(),r,e.context,e.renaming)),new ls(new hs(t.generateGoalId(),o,e.context,e.renaming))]),new Pt(t)}}}class Ns extends ws{constructor(t){super(t)}toString(){return"split"}apply(t){const e=t.getCurrentGoal().result;if(!(e.type.now()instanceof He))return new Tt(t.location,new vt([`"split" expected goal type to be Sigma, but got: ${e.type.prettyPrint()}`]));const n=e.type.now(),r=n.carType.now(),s=n.cdrType.valOfClosure(n);return t.addGoal([new ls(new hs(t.generateGoalId(),r,e.context,e.renaming)),new ls(new hs(t.generateGoalId(),s,e.context,e.renaming))]),new Pt(t)}}class xs extends ws{location;target;motive;constructor(t,e,n){super(t),this.location=t,this.target=e,this.motive=n}toString(){return`elim-absurd ${this.target} with motive ${this.motive.prettyPrint()}`}apply(t){const e=t.getCurrentGoal().result,n=e.context.get(this.target);if(!n)return new Tt(t.location,new vt([`target not found in current context: ${this.target}`]));let r;if(!(n instanceof Dt))throw new Error("Expected target to be a free variable");if(r=n.type.now(),!(r instanceof an))return new Tt(t.location,new vt([`Cannot eliminate non-Absurd type: ${r.prettyPrint()}`]));const s=this.motive.check(e.context,e.renaming,new en);return s instanceof Tt?s:(t.currentGoal.isComplete=!0,t.nextGoal(),new Pt(t))}}function _s(t,e){return[t,...e]}function ks(t){return new ut(t,!0)}function $s(t){return new mt(ks(t),t.source)}function Ss(t){if(t instanceof rt.Symbol)return t.value;if(t instanceof rt.NumericLiteral)return t.value;if(t instanceof st.List)return Ss(t.elements[0]);throw new Error("Expected a Element, but got: "+t)}function Os(t,e){return new ct(e.start,e.end,t)}function Ls(t,e){return Os(Ss(t),e)}function As(t){const e=new nt(t);return new at("",e.scanTokens()).parse()}class Is{static parsePie(t){return Is.parseElements(As(t)[0])}static parseElements(t){const e=Ss(t);if("U"===e)return n=Os("U",t.location),new dr(ks(n));if("the"===e){const e=t.elements;return function(t,e,n){return new yr(ks(t),e,n)}(Os("the",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("Nat"===e)return function(t){return new mr(ks(t))}(Os("Nat",t.location));if("zero"===e)return function(t){return new gr(ks(t))}(Os("zero",t.location));if("add1"===e)return function(t,e){return new vr(ks(t),e)}(Os("add1",t.location),this.parseElements(t.elements[1]));if("->"===e||"→"===e){const e=t.elements;return function(t,e){return new Nr(ks(t),e[0],e[1],e[2])}(Os("->",t.location),[this.parseElements(e[1]),this.parseElements(e[2]),e.slice(3).map(t=>this.parseElements(t))])}if("lambda"===e||"λ"===e){const e=t.elements,n=t.location,r=e[1],s=e[2];return function(t,e,n){return new _r(ks(t),e,n)}(Os("λ",n),r.elements.map(e=>$s(Ls(e,t.location))),this.parseElements(s))}if("Pi"===e||"Π"===e){const e=t.elements,n=e[1],r=e[2],s=n.elements[0],i=s.elements[0],a=s.elements[1],o=n.elements.slice(1).map(t=>{const e=t.elements[0],n=t.elements[1];return new gt($s(Ls(e,t.location)),this.parseElements(n))});return function(t,e,n){return new xr(ks(t),e,n)}(Os("Π",t.location),_s(new gt($s(Ls(i,s.location)),this.parseElements(a)),o),this.parseElements(r))}if("Sigma"===e||"Σ"===e){const e=t.elements,n=e[1],r=e[2],s=n.elements[0],i=s.elements[0],a=s.elements[1],o=n.elements.slice(1).map(t=>{const e=t.elements[0],n=t.elements[1];return new gt($s(Ls(e,t.location)),this.parseElements(n))});return function(t,e,n){return new kr(ks(t),e,n)}(Os("Π",t.location),_s(new gt($s(Ls(i,s.location)),this.parseElements(a)),o),this.parseElements(r))}if("Pair"===e){const e=t.elements;return function(t,e,n){return new Lr(ks(t),e,n)}(Os("Pair",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("cons"===e){const e=t.elements;return function(t,e,n){return new Ar(ks(t),e,n)}(Os("Cons",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("car"===e)return function(t,e){return new Ir(ks(t),e)}(Os("car",t.location),this.parseElements(t.elements[1]));if("cdr"===e)return function(t,e){return new Cr(ks(t),e)}(Os("cdr",t.location),this.parseElements(t.elements[1]));if("which-Nat"===e){const e=t.elements;return function(t,e,n,r){return new Er(ks(t),e,n,r)}(Os("which-Nat",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("iter-Nat"===e){const e=t.elements;return function(t,e,n,r){return new Pr(ks(t),e,n,r)}(Os("iter-Nat",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("rec-Nat"===e){const e=t.elements;return function(t,e,n,r){return new Tr(ks(t),e,n,r)}(Os("rec-Nat",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("ind-Nat"===e){const e=t.elements;return function(t,e,n,r,s){return new br(ks(t),e,n,r,s)}(Os("ind-Nat",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]),this.parseElements(e[4]))}if("Atom"===e)return function(t){return new Sr(ks(t))}(Os("Atom",t.location));if("quote"===e)return function(t,e){return new Or(ks(t),e)}(Os("Quote",t.location),Ss(t.elements[1]));if("Trivial"===e)return function(t){return new Br(ks(t))}(Os("Trivial",t.location));if("sole"===e)return function(t){return new Rr(ks(t))}(Os("sole",t.location));if("List"===e)return function(t,e){return new Gr(ks(t),e)}(Os("List",t.location),this.parseElements(t.elements[1]));if("nil"===e)return function(t){return new qr(ks(t))}(Os("nil",t.location));if("::"===e){const e=t.elements;return function(t,e,n){return new Ur(ks(t),e,n)}(Os("::",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("rec-List"===e){const e=t.elements;return function(t,e,n,r){return new Hr(ks(t),e,n,r)}(Os("rec-List",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("ind-List"===e){const e=t.elements;return function(t,e,n,r,s){return new zr(ks(t),e,n,r,s)}(Os("ind-List",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]),this.parseElements(e[4]))}if("="===e){const e=t.elements;return function(t,e,n,r){return new Qr(ks(t),e,n,r)}(Os("=",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("same"===e)return function(t,e){return new Vr(ks(t),e)}(Os("same",t.location),this.parseElements(t.elements[1]));if("replace"===e){const e=t.elements;return function(t,e,n,r){return new Xr(ks(t),e,n,r)}(Os("replace",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("trans"===e){const e=t.elements;return function(t,e,n){return new Kr(ks(t),e,n)}(Os("trans",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("cong"===e){const e=t.elements;return function(t,e,n){return new Yr(ks(t),e,n)}(Os("cong",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("ind-="===e){const e=t.elements;return function(t,e,n,r){return new Zr(ks(t),e,n,r)}(Os("ind-=",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]))}if("symm"===e)return function(t,e){return new jr(ks(t),e)}(Os("symm",t.location),this.parseElements(t.elements[1]));if("Vec"===e){const e=t.elements;return function(t,e,n){return new Wr(ks(t),e,n)}(Os("Vec",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("vecnil"===e)return function(t){return new Jr(ks(t))}(Os("vecnil",t.location));if("vec::"===e){const e=t.elements;return function(t,e,n){return new ts(ks(t),e,n)}(Os("vec::",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("head"===e)return function(t,e){return new es(ks(t),e)}(Os("head",t.location),this.parseElements(t.elements[1]));if("tail"===e)return function(t,e){return new ns(ks(t),e)}(Os("tail",t.location),this.parseElements(t.elements[1]));if("ind-Vec"===e){const e=t.elements;return function(t,e,n,r,s,i){return new rs(ks(t),e,n,r,s,i)}(Os("ind-Vec",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]),this.parseElements(e[4]),this.parseElements(e[5]))}if("Either"===e){const e=t.elements;return function(t,e,n){return new ss(ks(t),e,n)}(Os("Either",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("left"===e)return function(t,e){return new is(ks(t),e)}(Os("left",t.location),this.parseElements(t.elements[1]));if("right"===e)return function(t,e){return new as(ks(t),e)}(Os("right",t.location),this.parseElements(t.elements[1]));if("ind-Either"===e){const e=t.elements;return function(t,e,n,r,s){return new os(ks(t),e,n,r,s)}(Os("ind-Either",t.location),this.parseElements(e[1]),this.parseElements(e[2]),this.parseElements(e[3]),this.parseElements(e[4]))}if("Absurd"===e)return function(t){return new Dr(ks(t))}(Os("Absurd",t.location));if("ind-Absurd"===e){const e=t.elements;return function(t,e,n){return new Fr(ks(t),e,n)}(Os("ind-Absurd",t.location),this.parseElements(e[1]),this.parseElements(e[2]))}if("TODO"===e)return function(t){return new cs(ks(t))}(Os("TODO",t.location));if(t instanceof st.List&&t.elements.length>1){const e=t.elements;return function(t,e,n,r){return new us(ks(t),e,n,r)}(Os("App",t.location),this.parseElements(e[0]),this.parseElements(e[1]),e.slice(2).map(t=>this.parseElements(t)))}if($t(e))return function(t,e){return new $r(ks(t),e)}(Os(e,t.location),e);if(!isNaN(Number(e)))return function(t,e){return new Mr(ks(t),Number(e))}(Os(e,t.location),e);var n;throw new Error("Unexpected element: "+t)}static parseToTactics(t){const e=Ss(t);if("exact"===e)return n=Os("exact",t.location),r=this.parseElements(t.elements[1]),new ys(ks(n),r);if("intro"===e)return function(t,e){return new fs(ks(t),e)}(Os("intro",t.location),t.elements[1].value);if("exists"===e)return function(t,e,n){return new ds(ks(t),e,n)}(Os("exists",t.location),this.parseElements(t.elements[1]),t.elements[2].value);if("elimNat"===e)return function(t,e,n){return new ms(ks(t),e,n)}(Os("elimNat",t.location),t.elements[1].value,this.parseElements(t.elements[2]));if("elimList"===e)return function(t,e,n){return new gs(ks(t),e,n)}(Os("elimList",t.location),t.elements[1].value,this.parseElements(t.elements[2]));if("elimVec"===e)return function(t,e,n,r){return new vs(ks(t),e,n,r)}(Os("elimVec",t.location),t.elements[1].value,this.parseElements(t.elements[2]),this.parseElements(t.elements[3]));if("elimEqual"===e)return function(t,e,n){return new Es(ks(t),e,n)}(Os("elimEqual",t.location),t.elements[1].value,this.parseElements(t.elements[2]));if("left"===e)return function(t){return new Ps(ks(t))}(Os("left",t.location));if("right"===e)return function(t){return new Ts(ks(t))}(Os("right",t.location));if("elimEither"===e)return function(t,e,n){return new bs(ks(t),e,n)}(Os("elimEither",t.location),t.elements[1].value,this.parseElements(t.elements[2]));if("split"===e)return function(t){return new Ns(ks(t))}(Os("split",t.location));if("elimAbsurd"===e)return function(t,e,n){return new xs(ks(t),e,n)}(Os("elimAbsurd",t.location),t.elements[1].value,this.parseElements(t.elements[2]));var n,r;throw new Error("Unexpected tactic: "+t)}}class Cs{location;name;type;constructor(t,e,n){this.location=t,this.name=e,this.type=n}}class Bs{location;name;expr;constructor(t,e,n){this.location=t,this.name=e,this.expr=n}}class Rs{location;type;left;right;constructor(t,e,n,r){this.location=t,this.type=e,this.left=n,this.right=r}}class qs{location;name;tactics;constructor(t,e,n){this.location=t,this.name=e,this.tactics=n}}class Ms{static parseDeclaration(t){const e=Ss(t);if("claim"===e){const e=t.elements;return new Cs(ks(Ls(e[0],t.location)),Ss(e[1]),Is.parseElements(e[2]))}if("define"===e){const e=t.elements;return new Bs(ks(Ls(e[0],t.location)),Ss(e[1]),Is.parseElements(e[2]))}if("check-same"===e){const e=t.elements;return new Rs(ks(Ls(e[0],t.location)),Is.parseElements(e[1]),Is.parseElements(e[2]),Is.parseElements(e[3]))}if("define-tactically"===e){const e=t.elements;return new qs(ks(Ls(e[0],t.location)),Ss(e[1]),e[2].elements.map(t=>Is.parseToTactics(t)))}return Is.parseElements(t)}}function Gs(t,e){const n=new bt("outmeta");return Nt([[n,()=>e.synth(t,new Map)]],()=>{const e=Ct(t,n.value.type),r=Ct(t,n.value.expr);return new Pt(new cn(e.readBackType(t),se(t,e,r)))})}function Us(t,e,n,r,s){const i=new bt("tOut"),a=new bt("tv"),o=new bt("aOut"),c=new bt("bOut"),u=new bt("av"),h=new bt("bv");return Nt([[i,()=>n.isType(t,new Map)],[a,()=>Ct(t,i.value).readBackType(t)],[o,()=>r.check(t,new Map,a.value)],[c,()=>s.check(t,new Map,a.value)],[u,()=>Ct(t,o.value)],[h,()=>Ct(t,c.value)]],()=>ur(t,e,a.value,u.value,h.value))}function Hs(t){return t.prettyPrint()}class zs{currentState=null;startProof(t,e,n){const r=e.get(t);return r instanceof Ht?(this.currentState=ps.initialize(e,r.type,n),new Pt(`Started proof of ${t}\nCurrent goal: \n${r.type.readBackType(e).prettyPrint()}`)):new Tt(n,new vt([`${t} is not a valid type or has already been proved`]))}applyTactic(t){if(!this.currentState)return new Tt(t.location,new vt(["No proof has been initialized"]));const e=t.apply(this.currentState);if(e instanceof Tt)return e;this.currentState=e.result;let n=`\nApplied tactic: ${t}`;const r=this.currentState.getCurrentGoal();if(this.currentState.isComplete())n+="\nAll goals have been solved!";else{const t=r.result;n+="\nCurrent goal: \n"+t.type.readBackType(t.context).prettyPrint()}return new Pt(n)}}!function(t,e=self){const n=new c(e,!1);n.registerPlugin(m,t)}(class extends n{executionCount;constructor(t){super(t),this.executionCount=0}async evaluateChunk(t){this.executionCount++;try{const e=function(t){const e=As(t);let n=Gt,r="";for(const t of e){const e=Ms.parseDeclaration(t);if(e instanceof Cs){const t=Rt(n,e.name,e.location,e.type);if(t instanceof Pt)n=t.result;else if(t instanceof Tt)throw new Error(""+t.where+t.message)}else if(e instanceof Bs){const t=qt(n,e.name,e.location,e.expr);if(t instanceof Pt)n=t.result;else if(t instanceof Tt)throw new Error(""+t.where+t.message)}else if(e instanceof Rs){const t=Us(n,e.location,e.type,e.left,e.right);if(t instanceof Pt)n=t.result;else if(t instanceof Tt)throw new Error(""+t.where+t.message)}else{if(e instanceof qs){const t=new zs;let r="";const s=t.startProof(e.name,n,e.location);if(s instanceof Pt)r+=s.result+"\n";else if(s instanceof Tt)throw new Error(""+s.where+s.message);for(const n of e.tactics){const e=t.applyTactic(n);if(e instanceof Pt)r+=e.result;else if(e instanceof Tt)throw new Error(""+e.where+e.message)}return r}{const t=Gs(n,e);if(t instanceof Pt){const e=t.result;r+=`${Hs(e.expr)}: ${Hs(e.type)}\n`}else if(t instanceof Tt)throw new Error(`${t.message} at ${t.where}`)}}}for(const[t,e]of n)e instanceof zt?(r+=t+" : "+Hs(e.type.readBackType(n))+"\n",r+=t+" = "+Hs(se(n,e.type,e.value))+"\n"):r+=t+" : "+Hs(e.type.readBackType(n))+"\n";return r}(t);this.conductor.sendOutput(`Result of expression: execution ${e}`)}catch(t){t instanceof Error?this.conductor.sendOutput(`Error: ${t.message}`):this.conductor.sendOutput(`Error: ${String(t)}`)}}})}();
+//# sourceMappingURL=index.js.map
diff --git a/public/evaluators/py-slang/pyscript.js b/public/evaluators/py-slang/pyscript.js
new file mode 100644
index 0000000000..176a22a202
--- /dev/null
+++ b/public/evaluators/py-slang/pyscript.js
@@ -0,0 +1,1374 @@
+(function () {
+    'use strict';
+
+    /**
+     * Generic Conductor Error.
+     */
+    class ConductorError extends Error {
+        constructor(message) {
+            super(message);
+            this.name = "ConductorError";
+            this.errorType = "__unknown" /* ErrorType.UNKNOWN */;
+        }
+    }
+
+    /**
+     * Conductor internal error, probably caused by developer oversight.
+     */
+    class ConductorInternalError extends ConductorError {
+        constructor(message) {
+            super(message);
+            this.name = "ConductorInternalError";
+            this.errorType = "__internal" /* ErrorType.INTERNAL */;
+        }
+    }
+
+    class BasicEvaluator {
+        async startEvaluator(entryPoint) {
+            const initialChunk = await this.conductor.requestFile(entryPoint);
+            if (!initialChunk)
+                throw new ConductorInternalError("Cannot load entrypoint file");
+            await this.evaluateFile(entryPoint, initialChunk);
+            while (true) {
+                const chunk = await this.conductor.requestChunk();
+                await this.evaluateChunk(chunk);
+            }
+        }
+        /**
+         * Evaluates a file.
+         * @param fileName The name of the file to be evaluated.
+         * @param fileContent The content of the file to be evaluated.
+         * @returns A promise that resolves when the evaluation is complete.
+         */
+        async evaluateFile(fileName, fileContent) {
+            return this.evaluateChunk(fileContent);
+        }
+        constructor(conductor) {
+            this.conductor = conductor;
+        }
+    }
+
+    /******************************************************************************
+    Copyright (c) Microsoft Corporation.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose with or without fee is hereby granted.
+
+    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+    REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+    AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+    INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+    LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+    OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+    PERFORMANCE OF THIS SOFTWARE.
+    ***************************************************************************** */
+    /* global Reflect, Promise, SuppressedError, Symbol, Iterator */
+
+
+    function __esDecorate(ctor, descriptorIn, decorators, contextIn, initializers, extraInitializers) {
+        function accept(f) { if (f !== void 0 && typeof f !== "function") throw new TypeError("Function expected"); return f; }
+        var kind = contextIn.kind, key = kind === "getter" ? "get" : kind === "setter" ? "set" : "value";
+        var target = !descriptorIn && ctor ? contextIn["static"] ? ctor : ctor.prototype : null;
+        var descriptor = descriptorIn || (target ? Object.getOwnPropertyDescriptor(target, contextIn.name) : {});
+        var _, done = false;
+        for (var i = decorators.length - 1; i >= 0; i--) {
+            var context = {};
+            for (var p in contextIn) context[p] = p === "access" ? {} : contextIn[p];
+            for (var p in contextIn.access) context.access[p] = contextIn.access[p];
+            context.addInitializer = function (f) { if (done) throw new TypeError("Cannot add initializers after decoration has completed"); extraInitializers.push(accept(f || null)); };
+            var result = (0, decorators[i])(kind === "accessor" ? { get: descriptor.get, set: descriptor.set } : descriptor[key], context);
+            if (kind === "accessor") {
+                if (result === void 0) continue;
+                if (result === null || typeof result !== "object") throw new TypeError("Object expected");
+                if (_ = accept(result.get)) descriptor.get = _;
+                if (_ = accept(result.set)) descriptor.set = _;
+                if (_ = accept(result.init)) initializers.unshift(_);
+            }
+            else if (_ = accept(result)) {
+                if (kind === "field") initializers.unshift(_);
+                else descriptor[key] = _;
+            }
+        }
+        if (target) Object.defineProperty(target, contextIn.name, descriptor);
+        done = true;
+    }
+    function __runInitializers(thisArg, initializers, value) {
+        var useValue = arguments.length > 2;
+        for (var i = 0; i < initializers.length; i++) {
+            value = useValue ? initializers[i].call(thisArg, value) : initializers[i].call(thisArg);
+        }
+        return useValue ? value : void 0;
+    }
+    function __setFunctionName(f, name, prefix) {
+        if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+        return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
+    }
+    typeof SuppressedError === "function" ? SuppressedError : function (error, suppressed, message) {
+        var e = new Error(message);
+        return e.name = "SuppressedError", e.error = error, e.suppressed = suppressed, e;
+    };
+
+    /**
+     * Imports an external plugin from a given location.
+     * @param location Where to find the external plugin.
+     * @returns A promise resolving to the imported plugin.
+     */
+    async function importExternalPlugin(location) {
+        const plugin = (await import(/* webpackIgnore: true */ location)).plugin;
+        // TODO: verify it is actually a plugin
+        return plugin;
+    }
+
+    /**
+     * Imports an external module from a given location.
+     * @param location Where to find the external module.
+     * @returns A promise resolving to the imported module.
+     */
+    async function importExternalModule(location) {
+        const plugin = await importExternalPlugin(location);
+        // TODO: additional verification it is a module
+        return plugin;
+    }
+
+    class Channel {
+        send(message, transfer) {
+            this.__verifyAlive();
+            this.__port.postMessage(message, transfer ?? []);
+        }
+        subscribe(subscriber) {
+            this.__verifyAlive();
+            this.__subscribers.add(subscriber);
+            if (this.__waitingMessages) {
+                for (const data of this.__waitingMessages) {
+                    subscriber(data);
+                }
+                delete this.__waitingMessages;
+            }
+        }
+        unsubscribe(subscriber) {
+            this.__verifyAlive();
+            this.__subscribers.delete(subscriber);
+        }
+        close() {
+            this.__verifyAlive();
+            this.__isAlive = false;
+            this.__port?.close();
+        }
+        /**
+         * Check if this Channel is allowed to be used.
+         * @throws Throws an error if the Channel has been closed.
+         */
+        __verifyAlive() {
+            if (!this.__isAlive)
+                throw new ConductorInternalError(`Channel ${this.name} has been closed`);
+        }
+        /**
+         * Dispatch some data to subscribers.
+         * @param data The data to be dispatched to subscribers.
+         */
+        __dispatch(data) {
+            this.__verifyAlive();
+            if (this.__waitingMessages) {
+                // set a limit on how many setup messages to hold
+                // this prevents unlimited memory leak if the channel will never be listened to
+                if (this.__waitingMessages.length >= 10 /* Constant.SETUP_MESSAGES_BUFFER_SIZE */) {
+                    // not an error, since non-listening of channel is allowed by design
+                    return console.warn("Channel buffer full; message dropped (no subscribers on channel)", data);
+                }
+                this.__waitingMessages.push(data);
+            }
+            else {
+                for (const subscriber of this.__subscribers) {
+                    subscriber(data);
+                }
+            }
+        }
+        /**
+         * Listens to the port's message event, and starts the port.
+         * Messages will be buffered until the first subscriber listens to the Channel.
+         * @param port The MessagePort to listen to.
+         */
+        listenToPort(port) {
+            port.addEventListener("message", e => this.__dispatch(e.data));
+            port.start();
+        }
+        /**
+         * Replaces the underlying MessagePort of this Channel and closes it, and starts the new port.
+         * @param port The new port to use.
+         */
+        replacePort(port) {
+            this.__verifyAlive();
+            this.__port?.close();
+            this.__port = port;
+            this.listenToPort(port);
+        }
+        constructor(name, port) {
+            /** The callbacks subscribed to this Channel. */
+            this.__subscribers = new Set();
+            /** Is the Channel in a valid state? */
+            this.__isAlive = true;
+            /** Messages held temporarily while waiting for a listener. */
+            this.__waitingMessages = [];
+            this.name = name;
+            this.replacePort(port);
+        }
+    }
+
+    /**
+     * A stack-based queue implementation.
+     * `push` and `pop` run in amortized constant time.
+     */
+    class Queue {
+        constructor() {
+            /** The output stack. */
+            this.__s1 = [];
+            /** The input stack. */
+            this.__s2 = [];
+        }
+        /**
+         * Adds an item to the queue.
+         * @param item The item to be added to the queue.
+         */
+        push(item) {
+            this.__s2.push(item);
+        }
+        /**
+         * Removes an item from the queue.
+         * @returns The item removed from the queue.
+         * @throws If the queue is empty.
+         */
+        pop() {
+            if (this.__s1.length === 0) {
+                if (this.__s2.length === 0)
+                    throw new Error("queue is empty");
+                let temp = this.__s1;
+                this.__s1 = this.__s2.reverse();
+                this.__s2 = temp;
+            }
+            return this.__s1.pop(); // as the length is nonzero
+        }
+        /**
+         * The length of the queue.
+         */
+        get length() {
+            return this.__s1.length + this.__s2.length;
+        }
+        /**
+         * Makes a copy of the queue.
+         * @returns A copy of the queue.
+         */
+        clone() {
+            const newQueue = new Queue();
+            newQueue.__s1 = [...this.__s1];
+            newQueue.__s2 = [...this.__s2];
+            return newQueue;
+        }
+    }
+
+    class MessageQueue {
+        push(item) {
+            if (this.__promiseQueue.length !== 0)
+                this.__promiseQueue.pop()(item);
+            else
+                this.__inputQueue.push(item);
+        }
+        async pop() {
+            if (this.__inputQueue.length !== 0)
+                return this.__inputQueue.pop();
+            return new Promise((resolve, _reject) => {
+                this.__promiseQueue.push(resolve);
+            });
+        }
+        tryPop() {
+            if (this.__inputQueue.length !== 0)
+                return this.__inputQueue.pop();
+            return undefined;
+        }
+        constructor() {
+            this.__inputQueue = new Queue();
+            this.__promiseQueue = new Queue();
+            this.push = this.push.bind(this);
+        }
+    }
+
+    class ChannelQueue {
+        async receive() {
+            return this.__messageQueue.pop();
+        }
+        tryReceive() {
+            return this.__messageQueue.tryPop();
+        }
+        send(message, transfer) {
+            this.__channel.send(message, transfer);
+        }
+        close() {
+            this.__channel.unsubscribe(this.__messageQueue.push);
+        }
+        constructor(channel) {
+            this.__messageQueue = new MessageQueue();
+            this.name = channel.name;
+            this.__channel = channel;
+            this.__channel.subscribe(this.__messageQueue.push);
+        }
+    }
+
+    class Conduit {
+        __negotiateChannel(channelName) {
+            const { port1, port2 } = new MessageChannel();
+            const channel = new Channel(channelName, port1);
+            this.__link.postMessage([channelName, port2], [port2]); // TODO: update communication protocol?
+            this.__channels.set(channelName, channel);
+        }
+        __verifyAlive() {
+            if (!this.__alive)
+                throw new ConductorInternalError("Conduit already terminated");
+        }
+        registerPlugin(pluginClass, ...arg) {
+            this.__verifyAlive();
+            const attachedChannels = [];
+            for (const channelName of pluginClass.channelAttach) {
+                if (!this.__channels.has(channelName))
+                    this.__negotiateChannel(channelName);
+                attachedChannels.push(this.__channels.get(channelName)); // as the Channel has been negotiated
+            }
+            const plugin = new pluginClass(this, attachedChannels, ...arg);
+            if (plugin.name !== undefined) {
+                if (this.__pluginMap.has(plugin.name))
+                    throw new ConductorInternalError(`Plugin ${plugin.name} already registered`);
+                this.__pluginMap.set(plugin.name, plugin);
+            }
+            this.__plugins.push(plugin);
+            return plugin;
+        }
+        unregisterPlugin(plugin) {
+            this.__verifyAlive();
+            let p = 0;
+            for (let i = 0; i < this.__plugins.length; ++i) {
+                if (this.__plugins[p] === plugin)
+                    ++p;
+                this.__plugins[i] = this.__plugins[i + p];
+            }
+            for (let i = this.__plugins.length - 1, e = this.__plugins.length - p; i >= e; --i) {
+                delete this.__plugins[i];
+            }
+            if (plugin.name) {
+                this.__pluginMap.delete(plugin.name);
+            }
+            plugin.destroy?.();
+        }
+        lookupPlugin(pluginName) {
+            this.__verifyAlive();
+            if (!this.__pluginMap.has(pluginName))
+                throw new ConductorInternalError(`Plugin ${pluginName} not registered`);
+            return this.__pluginMap.get(pluginName); // as the map has been checked
+        }
+        terminate() {
+            this.__verifyAlive();
+            for (const plugin of this.__plugins) {
+                //this.unregisterPlugin(plugin);
+                plugin.destroy?.();
+            }
+            this.__link.terminate?.();
+            this.__alive = false;
+        }
+        __handlePort(data) {
+            const [channelName, port] = data;
+            if (this.__channels.has(channelName)) { // uh-oh, we already have a port for this channel
+                const channel = this.__channels.get(channelName); // as the map has been checked
+                if (this.__parent) { // extract the data and discard the messageport; child's Channel will close it
+                    channel.listenToPort(port);
+                }
+                else { // replace our messageport; Channel will close it
+                    channel.replacePort(port);
+                }
+            }
+            else { // register the new channel
+                const channel = new Channel(channelName, port);
+                this.__channels.set(channelName, channel);
+            }
+        }
+        constructor(link, parent = false) {
+            this.__alive = true;
+            this.__channels = new Map();
+            this.__pluginMap = new Map();
+            this.__plugins = [];
+            this.__link = link;
+            link.addEventListener("message", e => this.__handlePort(e.data));
+            this.__parent = parent;
+        }
+    }
+
+    class RpcCallMessage {
+        constructor(fn, args, invokeId) {
+            this.type = 0 /* RpcMessageType.CALL */;
+            this.data = { fn, args, invokeId };
+        }
+    }
+
+    class RpcErrorMessage {
+        constructor(invokeId, err) {
+            this.type = 2 /* RpcMessageType.RETURN_ERR */;
+            this.data = { invokeId, err };
+        }
+    }
+
+    class RpcReturnMessage {
+        constructor(invokeId, res) {
+            this.type = 1 /* RpcMessageType.RETURN */;
+            this.data = { invokeId, res };
+        }
+    }
+
+    function makeRpc(channel, self) {
+        const waiting = [];
+        let invocations = 0;
+        const otherCallbacks = {};
+        channel.subscribe(async (rpcMessage) => {
+            switch (rpcMessage.type) {
+                case 0 /* RpcMessageType.CALL */:
+                    {
+                        const { fn, args, invokeId } = rpcMessage.data;
+                        try {
+                            // @ts-expect-error
+                            const res = await self[fn](...args);
+                            if (invokeId > 0)
+                                channel.send(new RpcReturnMessage(invokeId, res));
+                        }
+                        catch (err) {
+                            if (invokeId > 0)
+                                channel.send(new RpcErrorMessage(invokeId, err));
+                        }
+                        break;
+                    }
+                case 1 /* RpcMessageType.RETURN */:
+                    {
+                        const { invokeId, res } = rpcMessage.data;
+                        waiting[invokeId]?.[0]?.(res);
+                        delete waiting[invokeId];
+                        break;
+                    }
+                case 2 /* RpcMessageType.RETURN_ERR */:
+                    {
+                        const { invokeId, err } = rpcMessage.data;
+                        waiting[invokeId]?.[1]?.(err);
+                        delete waiting[invokeId];
+                        break;
+                    }
+            }
+        });
+        return new Proxy(otherCallbacks, {
+            get(target, p, receiver) {
+                const cb = Reflect.get(target, p, receiver);
+                if (cb)
+                    return cb;
+                const newCallback = typeof p === "string" && p.charAt(0) === "$"
+                    ? (...args) => {
+                        channel.send(new RpcCallMessage(p, args, 0));
+                    }
+                    : (...args) => {
+                        const invokeId = ++invocations;
+                        channel.send(new RpcCallMessage(p, args, invokeId));
+                        return new Promise((resolve, reject) => {
+                            waiting[invokeId] = [resolve, reject];
+                        });
+                    };
+                Reflect.set(target, p, newCallback, receiver);
+                return newCallback;
+            },
+        });
+    }
+
+    /**
+     * Typechecking utility decorator.
+     * It is recommended that usage of this decorator is removed
+     * before or during the build process, as some tools
+     * (e.g. terser) do not have good support for class decorators.
+     * @param _pluginClass The Class to be typechecked.
+     */
+    function checkIsPluginClass(_pluginClass) {
+    }
+
+    var DataType;
+    (function (DataType) {
+        /** The return type of functions with no returned value. As a convention, the associated JS value is undefined. */
+        DataType[DataType["VOID"] = 0] = "VOID";
+        /** A Boolean value. */
+        DataType[DataType["BOOLEAN"] = 1] = "BOOLEAN";
+        /** A numerical value. */
+        DataType[DataType["NUMBER"] = 2] = "NUMBER";
+        /** An immutable string of characters. */
+        DataType[DataType["CONST_STRING"] = 3] = "CONST_STRING";
+        /** The empty list. As a convention, the associated JS value is null. */
+        DataType[DataType["EMPTY_LIST"] = 4] = "EMPTY_LIST";
+        /** A pair of values. Reference type. */
+        DataType[DataType["PAIR"] = 5] = "PAIR";
+        /** An array of values of a single type. Reference type. */
+        DataType[DataType["ARRAY"] = 6] = "ARRAY";
+        /** A value that can be called with fixed arity. Reference type. */
+        DataType[DataType["CLOSURE"] = 7] = "CLOSURE";
+        /** An opaque value that cannot be manipulated from user code. */
+        DataType[DataType["OPAQUE"] = 8] = "OPAQUE";
+        /** A list (either a pair or the empty list). */
+        DataType[DataType["LIST"] = 9] = "LIST";
+    })(DataType || (DataType = {}));
+
+    class AbortServiceMessage {
+        constructor(minVersion) {
+            this.type = 1 /* ServiceMessageType.ABORT */;
+            this.data = { minVersion: minVersion };
+        }
+    }
+
+    class HelloServiceMessage {
+        constructor() {
+            this.type = 0 /* ServiceMessageType.HELLO */;
+            this.data = { version: 0 /* Constant.PROTOCOL_VERSION */ };
+        }
+    }
+
+    class PluginServiceMessage {
+        constructor(pluginName) {
+            this.type = 3 /* ServiceMessageType.PLUGIN */;
+            this.data = pluginName;
+        }
+    }
+
+    let RunnerPlugin = (() => {
+        let _classDecorators = [checkIsPluginClass];
+        let _classDescriptor;
+        let _classExtraInitializers = [];
+        let _classThis;
+        _classThis = class {
+            requestFile(fileName) {
+                return this.__fileRpc.requestFile(fileName);
+            }
+            async requestChunk() {
+                return (await this.__chunkQueue.receive()).chunk;
+            }
+            async requestInput() {
+                const { message } = await this.__ioQueue.receive();
+                return message;
+            }
+            tryRequestInput() {
+                const out = this.__ioQueue.tryReceive();
+                return out?.message;
+            }
+            sendOutput(message) {
+                this.__ioQueue.send({ message });
+            }
+            sendError(error) {
+                this.__errorChannel.send({ error });
+            }
+            updateStatus(status, isActive) {
+                this.__statusChannel.send({ status, isActive });
+            }
+            hostLoadPlugin(pluginName) {
+                this.__serviceChannel.send(new PluginServiceMessage(pluginName));
+            }
+            registerPlugin(pluginClass, ...arg) {
+                return this.__conduit.registerPlugin(pluginClass, ...arg);
+            }
+            unregisterPlugin(plugin) {
+                this.__conduit.unregisterPlugin(plugin);
+            }
+            registerModule(moduleClass) {
+                if (!this.__isCompatibleWithModules)
+                    throw new ConductorInternalError("Evaluator has no data interface");
+                return this.registerPlugin(moduleClass, this.__evaluator);
+            }
+            unregisterModule(module) {
+                this.unregisterPlugin(module);
+            }
+            async importAndRegisterExternalPlugin(location, ...arg) {
+                const pluginClass = await importExternalPlugin(location);
+                return this.registerPlugin(pluginClass, ...arg);
+            }
+            async importAndRegisterExternalModule(location) {
+                const moduleClass = await importExternalModule(location);
+                return this.registerModule(moduleClass);
+            }
+            constructor(conduit, [fileChannel, chunkChannel, serviceChannel, ioChannel, errorChannel, statusChannel], evaluatorClass) {
+                this.name = "__runner_main" /* InternalPluginName.RUNNER_MAIN */;
+                // @ts-expect-error TODO: figure proper way to typecheck this
+                this.__serviceHandlers = new Map([
+                    [0 /* ServiceMessageType.HELLO */, function helloServiceHandler(message) {
+                            if (message.data.version < 0 /* Constant.PROTOCOL_MIN_VERSION */) {
+                                this.__serviceChannel.send(new AbortServiceMessage(0 /* Constant.PROTOCOL_MIN_VERSION */));
+                                console.error(`Host's protocol version (${message.data.version}) must be at least ${0 /* Constant.PROTOCOL_MIN_VERSION */}`);
+                            }
+                            else {
+                                console.log(`Host is using protocol version ${message.data.version}`);
+                            }
+                        }],
+                    [1 /* ServiceMessageType.ABORT */, function abortServiceHandler(message) {
+                            console.error(`Host expects at least protocol version ${message.data.minVersion}, but we are on version ${0 /* Constant.PROTOCOL_VERSION */}`);
+                            this.__conduit.terminate();
+                        }],
+                    [2 /* ServiceMessageType.ENTRY */, function entryServiceHandler(message) {
+                            this.__evaluator.startEvaluator(message.data);
+                        }]
+                ]);
+                this.__conduit = conduit;
+                this.__fileRpc = makeRpc(fileChannel, {});
+                this.__chunkQueue = new ChannelQueue(chunkChannel);
+                this.__serviceChannel = serviceChannel;
+                this.__ioQueue = new ChannelQueue(ioChannel);
+                this.__errorChannel = errorChannel;
+                this.__statusChannel = statusChannel;
+                this.__serviceChannel.send(new HelloServiceMessage());
+                this.__serviceChannel.subscribe(message => {
+                    this.__serviceHandlers.get(message.type)?.call(this, message);
+                });
+                this.__evaluator = new evaluatorClass(this);
+                this.__isCompatibleWithModules = this.__evaluator.hasDataInterface ?? false;
+            }
+        };
+        __setFunctionName(_classThis, "RunnerPlugin");
+        (() => {
+            const _metadata = typeof Symbol === "function" && Symbol.metadata ? Object.create(null) : void 0;
+            __esDecorate(null, _classDescriptor = { value: _classThis }, _classDecorators, { kind: "class", name: _classThis.name, metadata: _metadata }, null, _classExtraInitializers);
+            _classThis = _classDescriptor.value;
+            if (_metadata) Object.defineProperty(_classThis, Symbol.metadata, { enumerable: true, configurable: true, writable: true, value: _metadata });
+        })();
+        _classThis.channelAttach = ["__file_rpc" /* InternalChannelName.FILE */, "__chunk" /* InternalChannelName.CHUNK */, "__service" /* InternalChannelName.SERVICE */, "__stdio" /* InternalChannelName.STANDARD_IO */, "__error" /* InternalChannelName.ERROR */, "__status" /* InternalChannelName.STATUS */];
+        (() => {
+            __runInitializers(_classThis, _classExtraInitializers);
+        })();
+        return _classThis;
+    })();
+
+    /**
+     * Initialise this runner with the evaluator to be used.
+     * @param evaluatorClass The Evaluator to be used on this runner.
+     * @param link The underlying communication link.
+     * @returns The initialised `runnerPlugin` and `conduit`.
+     */
+    function initialise(evaluatorClass, link = self) {
+        const conduit = new Conduit(link, false);
+        const runnerPlugin = conduit.registerPlugin(RunnerPlugin, evaluatorClass);
+        return { runnerPlugin, conduit };
+    }
+
+    /**
+     * Configuration for Pyodide package management
+     *
+     * This file contains the list of packages that are available in the Pyodide distribution
+     * and can be loaded efficiently using pyodide.loadPackage()
+     */
+    /**
+     * List of packages available in Pyodide v0.26.2 distribution
+     * These packages are pre-compiled and optimized for WebAssembly
+     *
+     * Source: https://pyodide.org/en/stable/usage/packages-in-pyodide.html
+     */
+    const PYODIDE_BUILTIN_PACKAGES = new Set([
+        // Core scientific computing
+        'numpy',
+        'pandas',
+        'scipy',
+        'matplotlib',
+        'plotly',
+        'bokeh',
+        'seaborn',
+        // Machine learning
+        'scikit-learn',
+        'tensorflow',
+        'keras',
+        'pytorch',
+        'xgboost',
+        // Data processing
+        'pillow',
+        'opencv-python',
+        'beautifulsoup4',
+        'lxml',
+        'requests',
+        'urllib3',
+        // Numerical computing
+        'sympy',
+        'statsmodels',
+        'networkx',
+        // Package management
+        'micropip',
+        'pip',
+        // Development tools
+        'pytest',
+        'black',
+        'mypy',
+        // Other common packages
+        'dateutil',
+        'pytz',
+        'six',
+        'setuptools',
+        'wheel',
+        'packaging',
+        'certifi',
+        'charset-normalizer',
+        'idna',
+        'cycler',
+        'kiwisolver',
+        'pyparsing',
+        'fonttools',
+        // Jupyter ecosystem
+        'ipython',
+        'jupyter',
+        'notebook',
+        // Crypto/security
+        'cryptography',
+        'pycryptodome',
+        // File formats
+        'openpyxl',
+        'xlrd',
+        'h5py',
+        'tables',
+        // Visualization
+        'altair',
+        'plotnine',
+        'pygments',
+        // Statistics
+        'patsy',
+        'lifelines',
+        // Misc utilities
+        'joblib',
+        'tqdm',
+        'click',
+        'jinja2',
+        'markupsafe'
+    ]);
+    /**
+     * Essential packages that should always be available
+     * These are loaded at initialization for optimal performance
+     */
+    const ESSENTIAL_PACKAGES = [
+        'micropip' // Required for fallback package installation
+    ];
+    /**
+     * Packages that require special handling or have known issues
+     */
+    const SPECIAL_HANDLING_PACKAGES = new Map([
+        ['cv2', 'opencv-python'], // cv2 imports as opencv-python
+        ['PIL', 'pillow'], // PIL imports as pillow
+        ['sklearn', 'scikit-learn'], // sklearn imports as scikit-learn
+        ['torch', 'pytorch'], // torch imports as pytorch
+        ['tf', 'tensorflow'], // tf imports as tensorflow
+    ]);
+    /**
+     * Check if a package is available in Pyodide distribution
+     */
+    function isPyodideBuiltinPackage(packageName) {
+        // Check direct match
+        if (PYODIDE_BUILTIN_PACKAGES.has(packageName)) {
+            return true;
+        }
+        // Check special handling packages
+        if (SPECIAL_HANDLING_PACKAGES.has(packageName)) {
+            const actualPackage = SPECIAL_HANDLING_PACKAGES.get(packageName);
+            return PYODIDE_BUILTIN_PACKAGES.has(actualPackage);
+        }
+        return false;
+    }
+    /**
+     * Get the actual package name for Pyodide loading
+     */
+    function getPyodidePackageName(packageName) {
+        return SPECIAL_HANDLING_PACKAGES.get(packageName) ?? packageName;
+    }
+
+    /**
+     * Utilities for parsing Python import statements from code chunks
+     */
+    /**
+     * Extracts import statements from Python code using regex parsing
+     *
+     * This function identifies both 'import' and 'from...import' statements
+     * and extracts the relevant package information.
+     *
+     * @param code The Python code to parse
+     * @returns Array of ImportStatement objects
+     */
+    function extractImports(code) {
+        const imports = [];
+        const lines = code.split('\n');
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i].trim();
+            // Skip comments and empty lines
+            if (line.startsWith('#') || line.length === 0) {
+                continue;
+            }
+            // Handle regular import statements: import module [as alias]
+            const importMatch = line.match(/^import\s+([a-zA-Z0-9_][a-zA-Z0-9_.]*)(?:\s+as\s+([a-zA-Z0-9_]+))?/);
+            if (importMatch) {
+                imports.push({
+                    module: importMatch[1],
+                    alias: importMatch[2],
+                    isFromImport: false,
+                    line: i + 1
+                });
+                continue;
+            }
+            // Handle from imports: from module import item1, item2 [as alias]
+            const fromImportMatch = line.match(/^from\s+([a-zA-Z0-9_][a-zA-Z0-9_.]*)\s+import\s+(.+)/);
+            if (fromImportMatch) {
+                const module = fromImportMatch[1];
+                const importPart = fromImportMatch[2];
+                // Parse the imported items (handle commas, aliases, etc.)
+                const items = parseImportItems(importPart);
+                imports.push({
+                    module,
+                    items: items.map(item => item.name),
+                    isFromImport: true,
+                    line: i + 1
+                });
+                continue;
+            }
+        }
+        return imports;
+    }
+    /**
+     * Parses the items part of a 'from...import' statement
+     * Handles cases like: item1, item2 as alias, item3, *
+     */
+    function parseImportItems(importPart) {
+        const items = [];
+        // Split by comma and process each item
+        const parts = importPart.split(',').map(part => part.trim());
+        for (const part of parts) {
+            // Handle 'item as alias'
+            const aliasMatch = part.match(/^([a-zA-Z0-9_]+)\s+as\s+([a-zA-Z0-9_]+)$/);
+            if (aliasMatch) {
+                items.push({
+                    name: aliasMatch[1],
+                    alias: aliasMatch[2]
+                });
+                continue;
+            }
+            // Handle simple item name
+            const simpleMatch = part.match(/^([a-zA-Z0-9_*]+)$/);
+            if (simpleMatch) {
+                items.push({
+                    name: simpleMatch[1]
+                });
+            }
+        }
+        return items;
+    }
+    /**
+     * Extracts unique package names from a list of import statements
+     *
+     * For submodule imports like 'numpy.random', this returns the top-level package 'numpy'
+     *
+     * @param imports Array of ImportStatement objects
+     * @returns Set of unique package names
+     */
+    function extractPackageNames(imports) {
+        const packages = new Set();
+        for (const imp of imports) {
+            // Extract the top-level package name
+            const topLevelPackage = imp.module.split('.')[0];
+            // Skip built-in Python modules
+            if (!isBuiltinPythonModule(topLevelPackage)) {
+                packages.add(topLevelPackage);
+            }
+        }
+        return packages;
+    }
+    /**
+     * Checks if a module is a built-in Python module that doesn't need installation
+     */
+    function isBuiltinPythonModule(moduleName) {
+        const builtinModules = new Set([
+            'os', 'sys', 'json', 'math', 'random', 'datetime', 'time', 'collections',
+            'itertools', 'functools', 'operator', 'pathlib', 'glob', 'shutil', 'tempfile',
+            'urllib', 'http', 'html', 'xml', 'csv', 'configparser', 'logging', 'unittest',
+            'io', 're', 'string', 'textwrap', 'unicodedata', 'calendar', 'hashlib',
+            'hmac', 'secrets', 'statistics', 'decimal', 'fractions', 'contextlib',
+            'abc', 'numbers', 'types', 'copy', 'pprint', 'reprlib', 'enum', 'graphlib',
+            'weakref', 'gc', 'inspect', 'site', 'importlib', 'pkgutil', 'modulefinder',
+            'runpy', 'traceback', 'future', 'keyword', 'token', 'tokenize', 'ast',
+            'symtable', 'symbol', 'dis', 'pickletools', 'formatter', 'errno', 'ctypes',
+            'threading', 'multiprocessing', 'concurrent', 'subprocess', 'sched', 'queue',
+            'socketserver', 'ssl', 'asyncio', 'socket', 'signal', 'mmap', 'select',
+            'selectors', 'codecs', 'locale', 'gettext', 'argparse', 'optparse', 'getopt',
+            'cmd', 'shlex', 'platform', 'warnings', 'dataclasses', 'contextlib',
+            'typing', 'pydoc', 'doctest', 'difflib', 'rlcompleter', 'tabnanny', 'trace',
+            'timeit', 'cProfile', 'profile', 'pstats', 'cgi', 'cgitb', 'wsgiref',
+            'ftplib', 'poplib', 'imaplib', 'nntplib', 'smtplib', 'smtpd', 'telnetlib',
+            'uuid', 'zlib', 'gzip', 'bz2', 'lzma', 'zipfile', 'tarfile'
+        ]);
+        return builtinModules.has(moduleName);
+    }
+
+    /**
+     * Package Manager Service for Pyodide
+     *
+     * This service handles dynamic loading of Python packages using a hybrid approach:
+     * 1. Use pyodide.loadPackage() for built-in Pyodide packages (fast)
+     * 2. Use micropip.install() for PyPI packages (comprehensive)
+     *
+     * Features:
+     * - Intelligent package detection and classification
+     * - Caching to avoid redundant downloads
+     * - Comprehensive error handling and logging
+     * - Performance monitoring
+     */
+    class PackageManager {
+        constructor(pyodide, config = {}) {
+            this.micropipReady = false;
+            this.pyodide = pyodide;
+            this.cache = {
+                loaded: new Set(),
+                failed: new Map(),
+                loadTimestamps: new Map()
+            };
+            this.config = {
+                enableCaching: true,
+                loadTimeout: 30000, // 30 seconds
+                preloadEssentials: true,
+                verbose: false,
+                ...config
+            };
+        }
+        /**
+         * Initialize the package manager with essential packages
+         */
+        async initialize() {
+            if (this.config.verbose) {
+                console.log('[PackageManager] Initializing...');
+            }
+            if (this.config.preloadEssentials) {
+                await this.loadEssentialPackages();
+            }
+        }
+        /**
+         * Load essential packages that are always needed
+         */
+        async loadEssentialPackages() {
+            const startTime = Date.now();
+            for (const packageName of ESSENTIAL_PACKAGES) {
+                try {
+                    await this.loadSinglePackage(packageName);
+                    // Set up micropip after loading
+                    if (packageName === 'micropip') {
+                        this.micropipReady = true;
+                        if (this.config.verbose) {
+                            console.log('[PackageManager] micropip is ready');
+                        }
+                    }
+                }
+                catch (error) {
+                    console.warn(`[PackageManager] Failed to load essential package ${packageName}:`, error);
+                }
+            }
+            if (this.config.verbose) {
+                console.log(`[PackageManager] Essential packages loaded in ${Date.now() - startTime}ms`);
+            }
+        }
+        /**
+         * Analyze code and load all required packages
+         */
+        async loadPackagesFromCode(code) {
+            const startTime = Date.now();
+            if (this.config.verbose) {
+                console.log('[PackageManager] Analyzing code for imports...');
+            }
+            // Extract imports from code
+            const imports = extractImports(code);
+            const packageNames = extractPackageNames(imports);
+            if (this.config.verbose) {
+                console.log(`[PackageManager] Found ${packageNames.size} packages:`, Array.from(packageNames));
+            }
+            // Load packages
+            const results = await this.loadPackages(Array.from(packageNames));
+            if (this.config.verbose) {
+                const totalTime = Date.now() - startTime;
+                const successful = results.filter(r => r.success).length;
+                console.log(`[PackageManager] Loaded ${successful}/${results.length} packages in ${totalTime}ms`);
+            }
+            return results;
+        }
+        /**
+         * Load multiple packages using optimal strategy for each
+         */
+        async loadPackages(packageNames) {
+            const results = [];
+            // Process packages in parallel for better performance
+            const loadPromises = packageNames.map(async (packageName) => {
+                return await this.loadPackageWithStrategy(packageName);
+            });
+            const loadResults = await Promise.allSettled(loadPromises);
+            for (let i = 0; i < loadResults.length; i++) {
+                const result = loadResults[i];
+                if (result.status === 'fulfilled') {
+                    results.push(result.value);
+                }
+                else {
+                    results.push({
+                        packageName: packageNames[i],
+                        success: false,
+                        method: 'pyodide',
+                        error: result.reason?.message || 'Unknown error',
+                        loadTime: 0
+                    });
+                }
+            }
+            return results;
+        }
+        /**
+         * Load a single package using the optimal strategy
+         */
+        async loadPackageWithStrategy(packageName) {
+            const startTime = Date.now();
+            // Check cache first
+            if (this.config.enableCaching && this.cache.loaded.has(packageName)) {
+                return {
+                    packageName,
+                    success: true,
+                    method: 'pyodide', // This doesn't matter for cached packages
+                    loadTime: 0
+                };
+            }
+            // Check if package previously failed
+            if (this.config.enableCaching && this.cache.failed.has(packageName)) {
+                return {
+                    packageName,
+                    success: false,
+                    method: 'pyodide',
+                    error: this.cache.failed.get(packageName),
+                    loadTime: 0
+                };
+            }
+            try {
+                let result;
+                if (isPyodideBuiltinPackage(packageName)) {
+                    // Use Pyodide's built-in package loader
+                    result = await this.loadWithPyodide(packageName);
+                }
+                else {
+                    // Fall back to micropip for PyPI packages
+                    result = await this.loadWithMicropip(packageName);
+                }
+                // Update cache
+                if (this.config.enableCaching) {
+                    if (result.success) {
+                        this.cache.loaded.add(packageName);
+                        this.cache.loadTimestamps.set(packageName, Date.now());
+                    }
+                    else {
+                        this.cache.failed.set(packageName, result.error || 'Unknown error');
+                    }
+                }
+                result.loadTime = Date.now() - startTime;
+                return result;
+            }
+            catch (error) {
+                const errorMessage = error instanceof Error ? error.message : String(error);
+                if (this.config.enableCaching) {
+                    this.cache.failed.set(packageName, errorMessage);
+                }
+                return {
+                    packageName,
+                    success: false,
+                    method: 'pyodide',
+                    error: errorMessage,
+                    loadTime: Date.now() - startTime
+                };
+            }
+        }
+        /**
+         * Load package using Pyodide's built-in loader
+         */
+        async loadWithPyodide(packageName) {
+            const actualPackageName = getPyodidePackageName(packageName);
+            if (this.config.verbose) {
+                console.log(`[PackageManager] Loading ${packageName} (${actualPackageName}) via Pyodide...`);
+            }
+            try {
+                await this.pyodide.loadPackage(actualPackageName);
+                return {
+                    packageName,
+                    success: true,
+                    method: 'pyodide',
+                    loadTime: 0 // Will be set by caller
+                };
+            }
+            catch (error) {
+                throw new Error(`Pyodide failed to load ${actualPackageName}: ${error}`);
+            }
+        }
+        /**
+         * Load package using micropip from PyPI
+         */
+        async loadWithMicropip(packageName) {
+            if (!this.micropipReady) {
+                throw new Error('micropip is not ready. Ensure essential packages are loaded first.');
+            }
+            if (this.config.verbose) {
+                console.log(`[PackageManager] Loading ${packageName} via micropip...`);
+            }
+            try {
+                // Use micropip to install the package
+                await this.pyodide.runPythonAsync(`
+        import micropip
+        await micropip.install("${packageName}")
+      `);
+                return {
+                    packageName,
+                    success: true,
+                    method: 'micropip',
+                    loadTime: 0 // Will be set by caller
+                };
+            }
+            catch (error) {
+                throw new Error(`micropip failed to install ${packageName}: ${error}`);
+            }
+        }
+        /**
+         * Load a single package directly (for manual package loading)
+         */
+        async loadSinglePackage(packageName) {
+            return await this.loadPackageWithStrategy(packageName);
+        }
+        /**
+         * Get package loading statistics
+         */
+        getStats() {
+            const loadTimes = {};
+            for (const [pkg, timestamp] of this.cache.loadTimestamps) {
+                loadTimes[pkg] = timestamp;
+            }
+            return {
+                loaded: this.cache.loaded.size,
+                failed: this.cache.failed.size,
+                loadTimes
+            };
+        }
+        /**
+         * Clear the package cache
+         */
+        clearCache() {
+            this.cache.loaded.clear();
+            this.cache.failed.clear();
+            this.cache.loadTimestamps.clear();
+        }
+        /**
+         * Check if a package is already loaded
+         */
+        isPackageLoaded(packageName) {
+            return this.cache.loaded.has(packageName);
+        }
+        /**
+         * Get list of failed packages with their error messages
+         */
+        getFailedPackages() {
+            return new Map(this.cache.failed);
+        }
+    }
+
+    /**
+     * Enhanced Python Evaluator with Dynamic Package Loading
+     *
+     * This evaluator implements a hybrid approach for package management:
+     * - Analyzes code for import statements before execution
+     * - Loads required packages dynamically using optimal strategies
+     * - Provides comprehensive error handling and logging
+     * - Maintains backward compatibility with existing conductor framework
+     */
+    // Pyodide instance management
+    let pyodideInstance;
+    let pyodideReady;
+    let packageManager;
+    /**
+     * Initialize Pyodide and the package manager
+     */
+    async function ensurePyodideLoaded() {
+        if (!pyodideReady) {
+            console.log("[PythonEvaluator] Initializing Pyodide...");
+            try {
+                // Load pyodide from CDN in the worker scope
+                importScripts("https://cdn.jsdelivr.net/pyodide/v0.26.2/full/pyodide.js");
+            }
+            catch (e) {
+                console.error("[PythonEvaluator] Failed to import pyodide.js", e);
+                throw new Error("Failed to load Pyodide script");
+            }
+            pyodideReady = (async () => {
+                try {
+                    // Initialize Pyodide
+                    pyodideInstance = await loadPyodide({
+                        indexURL: "https://cdn.jsdelivr.net/pyodide/v0.26.2/full/"
+                    });
+                    // Initialize package manager with configuration
+                    const config = {
+                        enableCaching: true,
+                        loadTimeout: 30000,
+                        preloadEssentials: true,
+                        verbose: true // Enable for development, can be configured later
+                    };
+                    packageManager = new PackageManager(pyodideInstance, config);
+                    await packageManager.initialize();
+                    console.log("[PythonEvaluator] Pyodide and PackageManager initialized successfully");
+                }
+                catch (error) {
+                    console.error("[PythonEvaluator] Failed to initialize Pyodide:", error);
+                    throw error;
+                }
+            })();
+        }
+        return pyodideReady;
+    }
+    class PythonEvaluator extends BasicEvaluator {
+        constructor(conductor) {
+            super(conductor);
+        }
+        async evaluateChunk(chunk) {
+            console.log("[PythonEvaluator] Evaluating chunk:", chunk.substring(0, 100) + (chunk.length > 100 ? "..." : ""));
+            try {
+                // Ensure Pyodide is ready
+                await ensurePyodideLoaded();
+                if (!pyodideInstance || !packageManager) {
+                    throw new Error("Pyodide or PackageManager not properly initialized");
+                }
+                const pyodide = pyodideInstance;
+                // Set up I/O handling
+                this.setupIOHandling(pyodide);
+                // Load required packages before execution
+                await this.loadRequiredPackages(chunk);
+                // Execute the Python code
+                await this.executePythonCode(chunk);
+            }
+            catch (err) {
+                const message = this.formatError(err);
+                this.conductor.sendOutput(`[python error] ${message}`);
+                console.error("[PythonEvaluator] Execution error:", err);
+            }
+        }
+        /**
+         * Set up stdout/stderr handling and input function
+         */
+        setupIOHandling(pyodide) {
+            // Wire stdout to conductor output
+            pyodide.setStdout({
+                batched: (text) => {
+                    if (text)
+                        this.conductor.sendOutput(text);
+                }
+            });
+            // Provide synchronous input() backed by tryRequestInput()
+            const inputSync = (prompt) => {
+                if (typeof prompt === "string" && prompt.length > 0) {
+                    this.conductor.sendOutput(prompt);
+                }
+                const line = this.conductor.tryRequestInput();
+                return line ?? "";
+            };
+            // Expose the JS function to Python and override builtins.input
+            pyodide.globals.set("__sa_input_sync__", inputSync);
+            pyodide.runPython("import builtins\n" +
+                "builtins.input = __sa_input_sync__\n");
+        }
+        /**
+         * Analyze code and load required packages
+         */
+        async loadRequiredPackages(code) {
+            if (!packageManager) {
+                console.warn("[PythonEvaluator] PackageManager not available, skipping package loading");
+                return;
+            }
+            try {
+                const loadResults = await packageManager.loadPackagesFromCode(code);
+                // Report loading results
+                const successful = loadResults.filter(r => r.success);
+                const failed = loadResults.filter(r => !r.success);
+                if (successful.length > 0) {
+                    const successNames = successful.map(r => r.packageName).join(", ");
+                    console.log(`[PythonEvaluator] Successfully loaded packages: ${successNames}`);
+                }
+                if (failed.length > 0) {
+                    const failureDetails = failed.map(r => `${r.packageName} (${r.error})`).join(", ");
+                    console.warn(`[PythonEvaluator] Failed to load packages: ${failureDetails}`);
+                    // Send warning to user about failed packages
+                    this.conductor.sendOutput(`[warning] Some packages failed to load: ${failed.map(r => r.packageName).join(", ")}\n`);
+                }
+                // Log performance stats if any packages were loaded
+                if (loadResults.length > 0) {
+                    const totalTime = loadResults.reduce((sum, r) => sum + r.loadTime, 0);
+                    console.log(`[PythonEvaluator] Package loading completed in ${totalTime}ms`);
+                }
+            }
+            catch (error) {
+                console.error("[PythonEvaluator] Error during package loading:", error);
+                this.conductor.sendOutput(`[warning] Package loading encountered issues: ${error}\n`);
+            }
+        }
+        /**
+         * Execute Python code with proper error handling
+         */
+        async executePythonCode(code) {
+            if (!pyodideInstance) {
+                throw new Error("Pyodide instance not available");
+            }
+            try {
+                await pyodideInstance.runPythonAsync(code);
+            }
+            catch (error) {
+                // Re-throw with additional context
+                throw new Error(`Python execution failed: ${error}`);
+            }
+        }
+        /**
+         * Format error messages for user-friendly display
+         */
+        formatError(err) {
+            if (!err) {
+                return "Unknown error occurred";
+            }
+            // Extract meaningful error message
+            let message = "";
+            if (typeof err === "string") {
+                message = err;
+            }
+            else if (err.message) {
+                message = err.message;
+            }
+            else {
+                message = String(err);
+            }
+            // Clean up common error patterns for better readability
+            message = message
+                .replace(/^Error: /, "")
+                .replace(/^Python execution failed: /, "")
+                .replace(/PythonError: /, "");
+            return message;
+        }
+        /**
+         * Get package manager statistics (useful for debugging)
+         */
+        getPackageStats() {
+            if (!packageManager) {
+                return { error: "PackageManager not initialized" };
+            }
+            return packageManager.getStats();
+        }
+        /**
+         * Manually load a package (useful for testing or special cases)
+         */
+        async loadPackage(packageName) {
+            if (!packageManager) {
+                console.warn("[PythonEvaluator] PackageManager not available");
+                return false;
+            }
+            try {
+                const result = await packageManager.loadSinglePackage(packageName);
+                return result.success;
+            }
+            catch (error) {
+                console.error(`[PythonEvaluator] Failed to load package ${packageName}:`, error);
+                return false;
+            }
+        }
+    }
+
+    // Signal that the worker loaded
+    console.log("[py-pyscript] worker booted");
+    initialise(PythonEvaluator);
+
+})();
diff --git a/public/evaluators/py-slang/standard.js b/public/evaluators/py-slang/standard.js
new file mode 100644
index 0000000000..3b72e767d7
--- /dev/null
+++ b/public/evaluators/py-slang/standard.js
@@ -0,0 +1,722 @@
+(function () {
+    'use strict';
+
+    /**
+     * Generic Conductor Error.
+     */
+    class ConductorError extends Error {
+        constructor(message) {
+            super(message);
+            this.name = "ConductorError";
+            this.errorType = "__unknown" /* ErrorType.UNKNOWN */;
+        }
+    }
+
+    /**
+     * Conductor internal error, probably caused by developer oversight.
+     */
+    class ConductorInternalError extends ConductorError {
+        constructor(message) {
+            super(message);
+            this.name = "ConductorInternalError";
+            this.errorType = "__internal" /* ErrorType.INTERNAL */;
+        }
+    }
+
+    class BasicEvaluator {
+        async startEvaluator(entryPoint) {
+            const initialChunk = await this.conductor.requestFile(entryPoint);
+            if (!initialChunk)
+                throw new ConductorInternalError("Cannot load entrypoint file");
+            await this.evaluateFile(entryPoint, initialChunk);
+            while (true) {
+                const chunk = await this.conductor.requestChunk();
+                await this.evaluateChunk(chunk);
+            }
+        }
+        /**
+         * Evaluates a file.
+         * @param fileName The name of the file to be evaluated.
+         * @param fileContent The content of the file to be evaluated.
+         * @returns A promise that resolves when the evaluation is complete.
+         */
+        async evaluateFile(fileName, fileContent) {
+            return this.evaluateChunk(fileContent);
+        }
+        constructor(conductor) {
+            this.conductor = conductor;
+        }
+    }
+
+    /******************************************************************************
+    Copyright (c) Microsoft Corporation.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose with or without fee is hereby granted.
+
+    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+    REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+    AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+    INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+    LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+    OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+    PERFORMANCE OF THIS SOFTWARE.
+    ***************************************************************************** */
+    /* global Reflect, Promise, SuppressedError, Symbol, Iterator */
+
+
+    function __esDecorate(ctor, descriptorIn, decorators, contextIn, initializers, extraInitializers) {
+        function accept(f) { if (f !== void 0 && typeof f !== "function") throw new TypeError("Function expected"); return f; }
+        var kind = contextIn.kind, key = kind === "getter" ? "get" : kind === "setter" ? "set" : "value";
+        var target = !descriptorIn && ctor ? contextIn["static"] ? ctor : ctor.prototype : null;
+        var descriptor = descriptorIn || (target ? Object.getOwnPropertyDescriptor(target, contextIn.name) : {});
+        var _, done = false;
+        for (var i = decorators.length - 1; i >= 0; i--) {
+            var context = {};
+            for (var p in contextIn) context[p] = p === "access" ? {} : contextIn[p];
+            for (var p in contextIn.access) context.access[p] = contextIn.access[p];
+            context.addInitializer = function (f) { if (done) throw new TypeError("Cannot add initializers after decoration has completed"); extraInitializers.push(accept(f || null)); };
+            var result = (0, decorators[i])(kind === "accessor" ? { get: descriptor.get, set: descriptor.set } : descriptor[key], context);
+            if (kind === "accessor") {
+                if (result === void 0) continue;
+                if (result === null || typeof result !== "object") throw new TypeError("Object expected");
+                if (_ = accept(result.get)) descriptor.get = _;
+                if (_ = accept(result.set)) descriptor.set = _;
+                if (_ = accept(result.init)) initializers.unshift(_);
+            }
+            else if (_ = accept(result)) {
+                if (kind === "field") initializers.unshift(_);
+                else descriptor[key] = _;
+            }
+        }
+        if (target) Object.defineProperty(target, contextIn.name, descriptor);
+        done = true;
+    }
+    function __runInitializers(thisArg, initializers, value) {
+        var useValue = arguments.length > 2;
+        for (var i = 0; i < initializers.length; i++) {
+            value = useValue ? initializers[i].call(thisArg, value) : initializers[i].call(thisArg);
+        }
+        return useValue ? value : void 0;
+    }
+    function __setFunctionName(f, name, prefix) {
+        if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+        return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
+    }
+    typeof SuppressedError === "function" ? SuppressedError : function (error, suppressed, message) {
+        var e = new Error(message);
+        return e.name = "SuppressedError", e.error = error, e.suppressed = suppressed, e;
+    };
+
+    /**
+     * Imports an external plugin from a given location.
+     * @param location Where to find the external plugin.
+     * @returns A promise resolving to the imported plugin.
+     */
+    async function importExternalPlugin(location) {
+        const plugin = (await import(/* webpackIgnore: true */ location)).plugin;
+        // TODO: verify it is actually a plugin
+        return plugin;
+    }
+
+    /**
+     * Imports an external module from a given location.
+     * @param location Where to find the external module.
+     * @returns A promise resolving to the imported module.
+     */
+    async function importExternalModule(location) {
+        const plugin = await importExternalPlugin(location);
+        // TODO: additional verification it is a module
+        return plugin;
+    }
+
+    class Channel {
+        send(message, transfer) {
+            this.__verifyAlive();
+            this.__port.postMessage(message, transfer ?? []);
+        }
+        subscribe(subscriber) {
+            this.__verifyAlive();
+            this.__subscribers.add(subscriber);
+            if (this.__waitingMessages) {
+                for (const data of this.__waitingMessages) {
+                    subscriber(data);
+                }
+                delete this.__waitingMessages;
+            }
+        }
+        unsubscribe(subscriber) {
+            this.__verifyAlive();
+            this.__subscribers.delete(subscriber);
+        }
+        close() {
+            this.__verifyAlive();
+            this.__isAlive = false;
+            this.__port?.close();
+        }
+        /**
+         * Check if this Channel is allowed to be used.
+         * @throws Throws an error if the Channel has been closed.
+         */
+        __verifyAlive() {
+            if (!this.__isAlive)
+                throw new ConductorInternalError(`Channel ${this.name} has been closed`);
+        }
+        /**
+         * Dispatch some data to subscribers.
+         * @param data The data to be dispatched to subscribers.
+         */
+        __dispatch(data) {
+            this.__verifyAlive();
+            if (this.__waitingMessages) {
+                // set a limit on how many setup messages to hold
+                // this prevents unlimited memory leak if the channel will never be listened to
+                if (this.__waitingMessages.length >= 10 /* Constant.SETUP_MESSAGES_BUFFER_SIZE */) {
+                    // not an error, since non-listening of channel is allowed by design
+                    return console.warn("Channel buffer full; message dropped (no subscribers on channel)", data);
+                }
+                this.__waitingMessages.push(data);
+            }
+            else {
+                for (const subscriber of this.__subscribers) {
+                    subscriber(data);
+                }
+            }
+        }
+        /**
+         * Listens to the port's message event, and starts the port.
+         * Messages will be buffered until the first subscriber listens to the Channel.
+         * @param port The MessagePort to listen to.
+         */
+        listenToPort(port) {
+            port.addEventListener("message", e => this.__dispatch(e.data));
+            port.start();
+        }
+        /**
+         * Replaces the underlying MessagePort of this Channel and closes it, and starts the new port.
+         * @param port The new port to use.
+         */
+        replacePort(port) {
+            this.__verifyAlive();
+            this.__port?.close();
+            this.__port = port;
+            this.listenToPort(port);
+        }
+        constructor(name, port) {
+            /** The callbacks subscribed to this Channel. */
+            this.__subscribers = new Set();
+            /** Is the Channel in a valid state? */
+            this.__isAlive = true;
+            /** Messages held temporarily while waiting for a listener. */
+            this.__waitingMessages = [];
+            this.name = name;
+            this.replacePort(port);
+        }
+    }
+
+    /**
+     * A stack-based queue implementation.
+     * `push` and `pop` run in amortized constant time.
+     */
+    class Queue {
+        constructor() {
+            /** The output stack. */
+            this.__s1 = [];
+            /** The input stack. */
+            this.__s2 = [];
+        }
+        /**
+         * Adds an item to the queue.
+         * @param item The item to be added to the queue.
+         */
+        push(item) {
+            this.__s2.push(item);
+        }
+        /**
+         * Removes an item from the queue.
+         * @returns The item removed from the queue.
+         * @throws If the queue is empty.
+         */
+        pop() {
+            if (this.__s1.length === 0) {
+                if (this.__s2.length === 0)
+                    throw new Error("queue is empty");
+                let temp = this.__s1;
+                this.__s1 = this.__s2.reverse();
+                this.__s2 = temp;
+            }
+            return this.__s1.pop(); // as the length is nonzero
+        }
+        /**
+         * The length of the queue.
+         */
+        get length() {
+            return this.__s1.length + this.__s2.length;
+        }
+        /**
+         * Makes a copy of the queue.
+         * @returns A copy of the queue.
+         */
+        clone() {
+            const newQueue = new Queue();
+            newQueue.__s1 = [...this.__s1];
+            newQueue.__s2 = [...this.__s2];
+            return newQueue;
+        }
+    }
+
+    class MessageQueue {
+        push(item) {
+            if (this.__promiseQueue.length !== 0)
+                this.__promiseQueue.pop()(item);
+            else
+                this.__inputQueue.push(item);
+        }
+        async pop() {
+            if (this.__inputQueue.length !== 0)
+                return this.__inputQueue.pop();
+            return new Promise((resolve, _reject) => {
+                this.__promiseQueue.push(resolve);
+            });
+        }
+        tryPop() {
+            if (this.__inputQueue.length !== 0)
+                return this.__inputQueue.pop();
+            return undefined;
+        }
+        constructor() {
+            this.__inputQueue = new Queue();
+            this.__promiseQueue = new Queue();
+            this.push = this.push.bind(this);
+        }
+    }
+
+    class ChannelQueue {
+        async receive() {
+            return this.__messageQueue.pop();
+        }
+        tryReceive() {
+            return this.__messageQueue.tryPop();
+        }
+        send(message, transfer) {
+            this.__channel.send(message, transfer);
+        }
+        close() {
+            this.__channel.unsubscribe(this.__messageQueue.push);
+        }
+        constructor(channel) {
+            this.__messageQueue = new MessageQueue();
+            this.name = channel.name;
+            this.__channel = channel;
+            this.__channel.subscribe(this.__messageQueue.push);
+        }
+    }
+
+    class Conduit {
+        __negotiateChannel(channelName) {
+            const { port1, port2 } = new MessageChannel();
+            const channel = new Channel(channelName, port1);
+            this.__link.postMessage([channelName, port2], [port2]); // TODO: update communication protocol?
+            this.__channels.set(channelName, channel);
+        }
+        __verifyAlive() {
+            if (!this.__alive)
+                throw new ConductorInternalError("Conduit already terminated");
+        }
+        registerPlugin(pluginClass, ...arg) {
+            this.__verifyAlive();
+            const attachedChannels = [];
+            for (const channelName of pluginClass.channelAttach) {
+                if (!this.__channels.has(channelName))
+                    this.__negotiateChannel(channelName);
+                attachedChannels.push(this.__channels.get(channelName)); // as the Channel has been negotiated
+            }
+            const plugin = new pluginClass(this, attachedChannels, ...arg);
+            if (plugin.name !== undefined) {
+                if (this.__pluginMap.has(plugin.name))
+                    throw new ConductorInternalError(`Plugin ${plugin.name} already registered`);
+                this.__pluginMap.set(plugin.name, plugin);
+            }
+            this.__plugins.push(plugin);
+            return plugin;
+        }
+        unregisterPlugin(plugin) {
+            this.__verifyAlive();
+            let p = 0;
+            for (let i = 0; i < this.__plugins.length; ++i) {
+                if (this.__plugins[p] === plugin)
+                    ++p;
+                this.__plugins[i] = this.__plugins[i + p];
+            }
+            for (let i = this.__plugins.length - 1, e = this.__plugins.length - p; i >= e; --i) {
+                delete this.__plugins[i];
+            }
+            if (plugin.name) {
+                this.__pluginMap.delete(plugin.name);
+            }
+            plugin.destroy?.();
+        }
+        lookupPlugin(pluginName) {
+            this.__verifyAlive();
+            if (!this.__pluginMap.has(pluginName))
+                throw new ConductorInternalError(`Plugin ${pluginName} not registered`);
+            return this.__pluginMap.get(pluginName); // as the map has been checked
+        }
+        terminate() {
+            this.__verifyAlive();
+            for (const plugin of this.__plugins) {
+                //this.unregisterPlugin(plugin);
+                plugin.destroy?.();
+            }
+            this.__link.terminate?.();
+            this.__alive = false;
+        }
+        __handlePort(data) {
+            const [channelName, port] = data;
+            if (this.__channels.has(channelName)) { // uh-oh, we already have a port for this channel
+                const channel = this.__channels.get(channelName); // as the map has been checked
+                if (this.__parent) { // extract the data and discard the messageport; child's Channel will close it
+                    channel.listenToPort(port);
+                }
+                else { // replace our messageport; Channel will close it
+                    channel.replacePort(port);
+                }
+            }
+            else { // register the new channel
+                const channel = new Channel(channelName, port);
+                this.__channels.set(channelName, channel);
+            }
+        }
+        constructor(link, parent = false) {
+            this.__alive = true;
+            this.__channels = new Map();
+            this.__pluginMap = new Map();
+            this.__plugins = [];
+            this.__link = link;
+            link.addEventListener("message", e => this.__handlePort(e.data));
+            this.__parent = parent;
+        }
+    }
+
+    class RpcCallMessage {
+        constructor(fn, args, invokeId) {
+            this.type = 0 /* RpcMessageType.CALL */;
+            this.data = { fn, args, invokeId };
+        }
+    }
+
+    class RpcErrorMessage {
+        constructor(invokeId, err) {
+            this.type = 2 /* RpcMessageType.RETURN_ERR */;
+            this.data = { invokeId, err };
+        }
+    }
+
+    class RpcReturnMessage {
+        constructor(invokeId, res) {
+            this.type = 1 /* RpcMessageType.RETURN */;
+            this.data = { invokeId, res };
+        }
+    }
+
+    function makeRpc(channel, self) {
+        const waiting = [];
+        let invocations = 0;
+        const otherCallbacks = {};
+        channel.subscribe(async (rpcMessage) => {
+            switch (rpcMessage.type) {
+                case 0 /* RpcMessageType.CALL */:
+                    {
+                        const { fn, args, invokeId } = rpcMessage.data;
+                        try {
+                            // @ts-expect-error
+                            const res = await self[fn](...args);
+                            if (invokeId > 0)
+                                channel.send(new RpcReturnMessage(invokeId, res));
+                        }
+                        catch (err) {
+                            if (invokeId > 0)
+                                channel.send(new RpcErrorMessage(invokeId, err));
+                        }
+                        break;
+                    }
+                case 1 /* RpcMessageType.RETURN */:
+                    {
+                        const { invokeId, res } = rpcMessage.data;
+                        waiting[invokeId]?.[0]?.(res);
+                        delete waiting[invokeId];
+                        break;
+                    }
+                case 2 /* RpcMessageType.RETURN_ERR */:
+                    {
+                        const { invokeId, err } = rpcMessage.data;
+                        waiting[invokeId]?.[1]?.(err);
+                        delete waiting[invokeId];
+                        break;
+                    }
+            }
+        });
+        return new Proxy(otherCallbacks, {
+            get(target, p, receiver) {
+                const cb = Reflect.get(target, p, receiver);
+                if (cb)
+                    return cb;
+                const newCallback = typeof p === "string" && p.charAt(0) === "$"
+                    ? (...args) => {
+                        channel.send(new RpcCallMessage(p, args, 0));
+                    }
+                    : (...args) => {
+                        const invokeId = ++invocations;
+                        channel.send(new RpcCallMessage(p, args, invokeId));
+                        return new Promise((resolve, reject) => {
+                            waiting[invokeId] = [resolve, reject];
+                        });
+                    };
+                Reflect.set(target, p, newCallback, receiver);
+                return newCallback;
+            },
+        });
+    }
+
+    /**
+     * Typechecking utility decorator.
+     * It is recommended that usage of this decorator is removed
+     * before or during the build process, as some tools
+     * (e.g. terser) do not have good support for class decorators.
+     * @param _pluginClass The Class to be typechecked.
+     */
+    function checkIsPluginClass(_pluginClass) {
+    }
+
+    var DataType;
+    (function (DataType) {
+        /** The return type of functions with no returned value. As a convention, the associated JS value is undefined. */
+        DataType[DataType["VOID"] = 0] = "VOID";
+        /** A Boolean value. */
+        DataType[DataType["BOOLEAN"] = 1] = "BOOLEAN";
+        /** A numerical value. */
+        DataType[DataType["NUMBER"] = 2] = "NUMBER";
+        /** An immutable string of characters. */
+        DataType[DataType["CONST_STRING"] = 3] = "CONST_STRING";
+        /** The empty list. As a convention, the associated JS value is null. */
+        DataType[DataType["EMPTY_LIST"] = 4] = "EMPTY_LIST";
+        /** A pair of values. Reference type. */
+        DataType[DataType["PAIR"] = 5] = "PAIR";
+        /** An array of values of a single type. Reference type. */
+        DataType[DataType["ARRAY"] = 6] = "ARRAY";
+        /** A value that can be called with fixed arity. Reference type. */
+        DataType[DataType["CLOSURE"] = 7] = "CLOSURE";
+        /** An opaque value that cannot be manipulated from user code. */
+        DataType[DataType["OPAQUE"] = 8] = "OPAQUE";
+        /** A list (either a pair or the empty list). */
+        DataType[DataType["LIST"] = 9] = "LIST";
+    })(DataType || (DataType = {}));
+
+    class AbortServiceMessage {
+        constructor(minVersion) {
+            this.type = 1 /* ServiceMessageType.ABORT */;
+            this.data = { minVersion: minVersion };
+        }
+    }
+
+    class HelloServiceMessage {
+        constructor() {
+            this.type = 0 /* ServiceMessageType.HELLO */;
+            this.data = { version: 0 /* Constant.PROTOCOL_VERSION */ };
+        }
+    }
+
+    class PluginServiceMessage {
+        constructor(pluginName) {
+            this.type = 3 /* ServiceMessageType.PLUGIN */;
+            this.data = pluginName;
+        }
+    }
+
+    let RunnerPlugin = (() => {
+        let _classDecorators = [checkIsPluginClass];
+        let _classDescriptor;
+        let _classExtraInitializers = [];
+        let _classThis;
+        _classThis = class {
+            requestFile(fileName) {
+                return this.__fileRpc.requestFile(fileName);
+            }
+            async requestChunk() {
+                return (await this.__chunkQueue.receive()).chunk;
+            }
+            async requestInput() {
+                const { message } = await this.__ioQueue.receive();
+                return message;
+            }
+            tryRequestInput() {
+                const out = this.__ioQueue.tryReceive();
+                return out?.message;
+            }
+            sendOutput(message) {
+                this.__ioQueue.send({ message });
+            }
+            sendError(error) {
+                this.__errorChannel.send({ error });
+            }
+            updateStatus(status, isActive) {
+                this.__statusChannel.send({ status, isActive });
+            }
+            hostLoadPlugin(pluginName) {
+                this.__serviceChannel.send(new PluginServiceMessage(pluginName));
+            }
+            registerPlugin(pluginClass, ...arg) {
+                return this.__conduit.registerPlugin(pluginClass, ...arg);
+            }
+            unregisterPlugin(plugin) {
+                this.__conduit.unregisterPlugin(plugin);
+            }
+            registerModule(moduleClass) {
+                if (!this.__isCompatibleWithModules)
+                    throw new ConductorInternalError("Evaluator has no data interface");
+                return this.registerPlugin(moduleClass, this.__evaluator);
+            }
+            unregisterModule(module) {
+                this.unregisterPlugin(module);
+            }
+            async importAndRegisterExternalPlugin(location, ...arg) {
+                const pluginClass = await importExternalPlugin(location);
+                return this.registerPlugin(pluginClass, ...arg);
+            }
+            async importAndRegisterExternalModule(location) {
+                const moduleClass = await importExternalModule(location);
+                return this.registerModule(moduleClass);
+            }
+            constructor(conduit, [fileChannel, chunkChannel, serviceChannel, ioChannel, errorChannel, statusChannel], evaluatorClass) {
+                this.name = "__runner_main" /* InternalPluginName.RUNNER_MAIN */;
+                // @ts-expect-error TODO: figure proper way to typecheck this
+                this.__serviceHandlers = new Map([
+                    [0 /* ServiceMessageType.HELLO */, function helloServiceHandler(message) {
+                            if (message.data.version < 0 /* Constant.PROTOCOL_MIN_VERSION */) {
+                                this.__serviceChannel.send(new AbortServiceMessage(0 /* Constant.PROTOCOL_MIN_VERSION */));
+                                console.error(`Host's protocol version (${message.data.version}) must be at least ${0 /* Constant.PROTOCOL_MIN_VERSION */}`);
+                            }
+                            else {
+                                console.log(`Host is using protocol version ${message.data.version}`);
+                            }
+                        }],
+                    [1 /* ServiceMessageType.ABORT */, function abortServiceHandler(message) {
+                            console.error(`Host expects at least protocol version ${message.data.minVersion}, but we are on version ${0 /* Constant.PROTOCOL_VERSION */}`);
+                            this.__conduit.terminate();
+                        }],
+                    [2 /* ServiceMessageType.ENTRY */, function entryServiceHandler(message) {
+                            this.__evaluator.startEvaluator(message.data);
+                        }]
+                ]);
+                this.__conduit = conduit;
+                this.__fileRpc = makeRpc(fileChannel, {});
+                this.__chunkQueue = new ChannelQueue(chunkChannel);
+                this.__serviceChannel = serviceChannel;
+                this.__ioQueue = new ChannelQueue(ioChannel);
+                this.__errorChannel = errorChannel;
+                this.__statusChannel = statusChannel;
+                this.__serviceChannel.send(new HelloServiceMessage());
+                this.__serviceChannel.subscribe(message => {
+                    this.__serviceHandlers.get(message.type)?.call(this, message);
+                });
+                this.__evaluator = new evaluatorClass(this);
+                this.__isCompatibleWithModules = this.__evaluator.hasDataInterface ?? false;
+            }
+        };
+        __setFunctionName(_classThis, "RunnerPlugin");
+        (() => {
+            const _metadata = typeof Symbol === "function" && Symbol.metadata ? Object.create(null) : void 0;
+            __esDecorate(null, _classDescriptor = { value: _classThis }, _classDecorators, { kind: "class", name: _classThis.name, metadata: _metadata }, null, _classExtraInitializers);
+            _classThis = _classDescriptor.value;
+            if (_metadata) Object.defineProperty(_classThis, Symbol.metadata, { enumerable: true, configurable: true, writable: true, value: _metadata });
+        })();
+        _classThis.channelAttach = ["__file_rpc" /* InternalChannelName.FILE */, "__chunk" /* InternalChannelName.CHUNK */, "__service" /* InternalChannelName.SERVICE */, "__stdio" /* InternalChannelName.STANDARD_IO */, "__error" /* InternalChannelName.ERROR */, "__status" /* InternalChannelName.STATUS */];
+        (() => {
+            __runInitializers(_classThis, _classExtraInitializers);
+        })();
+        return _classThis;
+    })();
+
+    /**
+     * Initialise this runner with the evaluator to be used.
+     * @param evaluatorClass The Evaluator to be used on this runner.
+     * @param link The underlying communication link.
+     * @returns The initialised `runnerPlugin` and `conduit`.
+     */
+    function initialise(evaluatorClass, link = self) {
+        const conduit = new Conduit(link, false);
+        const runnerPlugin = conduit.registerPlugin(RunnerPlugin, evaluatorClass);
+        return { runnerPlugin, conduit };
+    }
+
+    // Load Pyodide inside the worker and initialise once
+    let pyodideInstance;
+    let pyodideReady;
+    function ensurePyodideLoaded() {
+        if (!pyodideReady) {
+            console.log("[runner] ensurePyodideLoaded entered");
+            try {
+                // Load pyodide from CDN in the worker scope
+                importScripts("https://cdn.jsdelivr.net/pyodide/v0.26.2/full/pyodide.js");
+            }
+            catch (e) {
+                // If importScripts is unavailable for some reason, surface the error later
+                console.error("Failed to import pyodide.js", e);
+            }
+            pyodideReady = (async () => {
+                // @ts-ignore loadPyodide is provided by the imported script
+                pyodideInstance = await loadPyodide({ indexURL: "https://cdn.jsdelivr.net/pyodide/v0.26.2/full/" });
+                await pyodideInstance.loadPackage("pandas");
+            })();
+        }
+        return pyodideReady;
+    }
+    class PythonEvaluator extends BasicEvaluator {
+        constructor(conductor) {
+            super(conductor);
+        }
+        async evaluateChunk(chunk) {
+            console.log("[runner] evaluateChunk entered with chunk: ", chunk);
+            await ensurePyodideLoaded();
+            console.log("[runner] ensurePyodideLoaded exited");
+            const pyodide = pyodideInstance;
+            // Wire stdout/stderr to conductor output
+            pyodide.setStdout({
+                batched: (text) => {
+                    if (text)
+                        this.conductor.sendOutput(text);
+                }
+            });
+            // pyodide.setStderr({
+            // 	batched: (text: string) => {
+            // 		if (text) this.conductor.sendOutput(text);
+            // 	}
+            // });
+            // Provide a synchronous input() backed by tryRequestInput()
+            // If no input is available, return empty string to avoid blocking
+            const inputSync = (prompt) => {
+                if (typeof prompt === "string" && prompt.length > 0) {
+                    this.conductor.sendOutput(prompt);
+                }
+                const line = this.conductor.tryRequestInput();
+                return line ?? "";
+            };
+            // Expose the JS function to Python and override builtins.input
+            pyodide.globals.set("__sa_input_sync__", inputSync);
+            pyodide.runPython("import builtins\n" +
+                "builtins.input = __sa_input_sync__\n");
+            try {
+                await pyodide.runPythonAsync(chunk);
+            }
+            catch (err) {
+                const message = (err && err.message) ? err.message : String(err);
+                this.conductor.sendOutput(`[python error] ${message}`);
+            }
+        }
+    }
+    // Signal that the worker loaded
+    console.log("[py-pyscript] worker booted");
+    initialise(PythonEvaluator);
+
+})();
+//# sourceMappingURL=worker.js.map
diff --git a/src/commons/application/ApplicationTypes.ts b/src/commons/application/ApplicationTypes.ts
index d6984afa63..4524a67eae 100644
--- a/src/commons/application/ApplicationTypes.ts
+++ b/src/commons/application/ApplicationTypes.ts
@@ -2,6 +2,7 @@ import { Chapter, Language, type SourceError, type Value, Variant } from 'js-sla
 
 import type { AchievementState } from '../../features/achievement/AchievementTypes';
 import type { DashboardState } from '../../features/dashboard/DashboardTypes';
+import type { LanguageDirectoryState } from '../../features/languageDirectory/LanguageDirectoryTypes';
 import type { LeaderboardState } from '../../features/leaderboard/LeaderboardTypes';
 import type { PlaygroundState } from '../../features/playground/PlaygroundTypes';
 import { PlaybackStatus, RecordingStatus } from '../../features/sourceRecorder/SourceRecorderTypes';
@@ -37,6 +38,7 @@ export type OverallState = {
   readonly fileSystem: FileSystemState;
   readonly sideContent: SideContentManagerState;
   readonly vscode: VscodeState;
+  readonly languageDirectory: LanguageDirectoryState;
 };
 
 export type Story = {
@@ -613,6 +615,12 @@ export const defaultVscode: VscodeState = {
   isVscode: false
 };
 
+export const defaultLanguageDirectory: LanguageDirectoryState = {
+  selectedLanguageId: null,
+  selectedEvaluatorId: null,
+  languages: []
+};
+
 export const defaultState: OverallState = {
   router: defaultRouter,
   achievement: defaultAchievement,
@@ -625,5 +633,6 @@ export const defaultState: OverallState = {
   featureFlags: defaultFeatureFlags,
   fileSystem: defaultFileSystem,
   sideContent: defaultSideContentManager,
-  vscode: defaultVscode
+  vscode: defaultVscode,
+  languageDirectory: defaultLanguageDirectory
 };
diff --git a/src/commons/application/reducers/RootReducer.ts b/src/commons/application/reducers/RootReducer.ts
index 4c89cf6377..7805880190 100644
--- a/src/commons/application/reducers/RootReducer.ts
+++ b/src/commons/application/reducers/RootReducer.ts
@@ -1,14 +1,15 @@
-import { combineReducers, Reducer } from '@reduxjs/toolkit';
-import { SourceActionType } from 'src/commons/utils/ActionsHelper';
+import { combineReducers, type Reducer } from '@reduxjs/toolkit';
 
 import { FeatureFlagsReducer as featureFlags } from '../../..//commons/featureFlags';
 import { AchievementReducer as achievement } from '../../../features/achievement/AchievementReducer';
 import { DashboardReducer as dashboard } from '../../../features/dashboard/DashboardReducer';
+import { LanguageDirectoryReducer as languageDirectory } from '../../../features/languageDirectory/LanguageDirectoryReducer';
 import { LeaderboardReducer as leaderboard } from '../../../features/leaderboard/LeaderboardReducer';
 import { PlaygroundReducer as playground } from '../../../features/playground/PlaygroundReducer';
 import { StoriesReducer as stories } from '../../../features/stories/StoriesReducer';
 import { FileSystemReducer as fileSystem } from '../../fileSystem/FileSystemReducer';
 import { SideContentReducer as sideContent } from '../../sideContent/SideContentReducer';
+import type { SourceActionType } from '../../utils/ActionsHelper';
 import { WorkspaceReducer as workspaces } from '../../workspace/WorkspaceReducer';
 import { OverallState } from '../ApplicationTypes';
 import { RouterReducer as router } from './CommonsReducer';
@@ -27,7 +28,8 @@ const rootReducer: Reducer<OverallState, SourceActionType> = combineReducers({
   featureFlags,
   fileSystem,
   sideContent,
-  vscode
+  vscode,
+  languageDirectory
 });
 
 export default rootReducer;
diff --git a/src/commons/controlBar/ControlBarChapterSelect.tsx b/src/commons/controlBar/ControlBarChapterSelect.tsx
index c35be486ca..c593f61989 100644
--- a/src/commons/controlBar/ControlBarChapterSelect.tsx
+++ b/src/commons/controlBar/ControlBarChapterSelect.tsx
@@ -1,22 +1,17 @@
-import { Button, Menu, MenuItem, Tooltip } from '@blueprintjs/core';
+import { Button, Menu, MenuItem } from '@blueprintjs/core';
 import { IconNames } from '@blueprintjs/icons';
 import { ItemListRenderer, ItemRenderer, Select } from '@blueprintjs/select';
 import { Chapter, Variant } from 'js-slang/dist/types';
-import React from 'react';
+import React, { useEffect } from 'react';
+import { useDispatch } from 'react-redux';
 
-import {
-  fullJSLanguage,
-  fullTSLanguage,
-  htmlLanguage,
-  javaLanguages,
-  pyLanguages,
-  SALanguage,
-  schemeLanguages,
-  sourceLanguages,
-  styliseSublanguage
-} from '../application/ApplicationTypes';
-import Constants from '../utils/Constants';
+import { flagLanguageDirectoryEnable } from '../../features/languageDirectory/flagLanguageDirectory';
+import LanguageDirectoryActions from '../../features/languageDirectory/LanguageDirectoryActions';
+import type { IEvaluatorDefinition } from '../../features/languageDirectory/LanguageDirectoryTypes';
+import { SALanguage } from '../application/ApplicationTypes';
+import { useFeature } from '../featureFlags/useFeature';
 import { useTypedSelector } from '../utils/Hooks';
+import { LegacyControlBarChapterSelect } from './LegacyControlBarChapterSelect';
 
 type ControlBarChapterSelectProps = DispatchProps & StateProps;
 
@@ -31,46 +26,6 @@ type StateProps = {
   disabled?: boolean;
 };
 
-const chapterListRenderer: ItemListRenderer<SALanguage> = ({
-  itemsParentRef,
-  renderItem,
-  items
-}) => {
-  const defaultChoices = items.filter(({ variant }) => variant === Variant.DEFAULT);
-  const variantChoices = items.filter(({ variant }) => variant !== Variant.DEFAULT);
-
-  return (
-    <Menu ulRef={itemsParentRef} style={{ display: 'flex', flexDirection: 'column' }}>
-      {defaultChoices.map(renderItem)}
-      {variantChoices.length > 0 && (
-        <MenuItem key="variant-menu" text="Variants" icon="cog">
-          {variantChoices.map(renderItem)}
-        </MenuItem>
-      )}
-    </Menu>
-  );
-};
-
-const chapterRenderer: (isFolderModeEnabled: boolean) => ItemRenderer<SALanguage> =
-  (isFolderModeEnabled: boolean) =>
-  (lang, { handleClick }) => {
-    const isDisabled = isFolderModeEnabled && lang.chapter === Chapter.SOURCE_1;
-    const tooltipContent = isDisabled
-      ? 'Folder mode makes use of lists which are not available in Source 1. To switch to Source 1, disable Folder mode.'
-      : undefined;
-    return (
-      <Tooltip
-        key={lang.displayName}
-        content={tooltipContent}
-        disabled={tooltipContent === undefined}
-      >
-        <MenuItem onClick={handleClick} text={lang.displayName} disabled={isDisabled} />
-      </Tooltip>
-    );
-  };
-
-const ChapterSelectComponent = Select.ofType<SALanguage>();
-
 export const ControlBarChapterSelect: React.FC<ControlBarChapterSelectProps> = ({
   isFolderModeEnabled,
   sourceChapter,
@@ -78,34 +33,70 @@ export const ControlBarChapterSelect: React.FC<ControlBarChapterSelectProps> = (
   handleChapterSelect = () => {},
   disabled = false
 }) => {
-  const selectedLang = useTypedSelector(store => store.playground.languageConfig.mainLanguage);
+  const dispatch = useDispatch();
+  const directoryEnabled = useFeature(flagLanguageDirectoryEnable);
+  const selectedLanguageId = useTypedSelector(s => s.languageDirectory.selectedLanguageId);
+  const selectedEvaluatorId = useTypedSelector(s => s.languageDirectory.selectedEvaluatorId);
+  const dirLanguages = useTypedSelector(s => s.languageDirectory.languages);
+
+  useEffect(() => {
+    if (directoryEnabled && dirLanguages.length === 0) {
+      dispatch(LanguageDirectoryActions.fetchLanguages());
+    }
+  }, [directoryEnabled, dirLanguages.length, dispatch]);
 
-  const choices = [
-    ...sourceLanguages,
-    // Full JS/TS version uses eval(), which is a huge security risk, so we only enable
-    // for public deployments. HTML, while sandboxed, is treated the same way to be safe.
-    // See https://github.com/source-academy/frontend/pull/2460#issuecomment-1528759912
-    ...(Constants.playgroundOnly ? [fullJSLanguage, fullTSLanguage, htmlLanguage] : []),
-    ...schemeLanguages,
-    ...pyLanguages,
-    ...javaLanguages
-  ];
+  if (!directoryEnabled) {
+    return (
+      <LegacyControlBarChapterSelect
+        isFolderModeEnabled={isFolderModeEnabled}
+        sourceChapter={sourceChapter}
+        sourceVariant={sourceVariant}
+        handleChapterSelect={handleChapterSelect}
+        disabled={disabled}
+      />
+    );
+  }
+
+  const EvaluatorSelectComponent = Select.ofType<IEvaluatorDefinition>();
+
+  const currentLanguage = dirLanguages.find(l => l.id === selectedLanguageId);
+  const evaluators = currentLanguage?.evaluators ?? [];
+  const selectedEvaluator = evaluators.find(e => e.id === selectedEvaluatorId);
+
+  const evaluatorListRenderer: ItemListRenderer<IEvaluatorDefinition> = ({
+    itemsParentRef,
+    renderItem,
+    items
+  }) => (
+    <Menu ulRef={itemsParentRef} style={{ display: 'flex', flexDirection: 'column' }}>
+      {items.map(renderItem)}
+    </Menu>
+  );
+
+  const evaluatorRenderer: ItemRenderer<IEvaluatorDefinition> = (evaluator, { handleClick }) => (
+    <MenuItem key={evaluator.id} onClick={handleClick} text={evaluator.name} />
+  );
+
+  const onSelectEvaluator = (evaluator: IEvaluatorDefinition) => {
+    dispatch(LanguageDirectoryActions.setSelectedEvaluator(evaluator.id));
+  };
 
   return (
-    <ChapterSelectComponent
-      items={choices.filter(({ mainLanguage }) => mainLanguage === selectedLang)}
-      onItemSelect={handleChapterSelect}
-      itemRenderer={chapterRenderer(isFolderModeEnabled)}
-      itemListRenderer={chapterListRenderer}
+    <EvaluatorSelectComponent
+      items={evaluators}
+      onItemSelect={onSelectEvaluator}
+      itemRenderer={evaluatorRenderer}
+      itemListRenderer={evaluatorListRenderer}
       filterable={false}
       disabled={disabled}
     >
       <Button
         minimal
-        text={styliseSublanguage(sourceChapter, sourceVariant)}
+        text={selectedEvaluator ? selectedEvaluator.name : 'Select Evaluator'}
         rightIcon={disabled ? null : IconNames.DOUBLE_CARET_VERTICAL}
+        data-testid="ControlBarEvaluatorSelect"
         disabled={disabled}
       />
-    </ChapterSelectComponent>
+    </EvaluatorSelectComponent>
   );
 };
diff --git a/src/commons/controlBar/LegacyControlBarChapterSelect.tsx b/src/commons/controlBar/LegacyControlBarChapterSelect.tsx
new file mode 100644
index 0000000000..b717c40082
--- /dev/null
+++ b/src/commons/controlBar/LegacyControlBarChapterSelect.tsx
@@ -0,0 +1,111 @@
+import { Button, Menu, MenuItem, Tooltip } from '@blueprintjs/core';
+import { IconNames } from '@blueprintjs/icons';
+import { ItemListRenderer, ItemRenderer, Select } from '@blueprintjs/select';
+import { Chapter, Variant } from 'js-slang/dist/types';
+import React from 'react';
+
+import {
+  fullJSLanguage,
+  fullTSLanguage,
+  htmlLanguage,
+  javaLanguages,
+  pyLanguages,
+  SALanguage,
+  schemeLanguages,
+  sourceLanguages,
+  styliseSublanguage
+} from '../application/ApplicationTypes';
+import Constants from '../utils/Constants';
+import { useTypedSelector } from '../utils/Hooks';
+
+type ControlBarChapterSelectProps = DispatchProps & StateProps;
+
+type DispatchProps = {
+  handleChapterSelect?: (i: SALanguage, e?: React.SyntheticEvent<HTMLElement>) => void;
+};
+
+type StateProps = {
+  isFolderModeEnabled: boolean;
+  sourceChapter: Chapter;
+  sourceVariant: Variant;
+  disabled?: boolean;
+};
+
+const chapterListRenderer: ItemListRenderer<SALanguage> = ({
+  itemsParentRef,
+  renderItem,
+  items
+}) => {
+  const defaultChoices = items.filter(({ variant }) => variant === Variant.DEFAULT);
+  const variantChoices = items.filter(({ variant }) => variant !== Variant.DEFAULT);
+
+  return (
+    <Menu ulRef={itemsParentRef} style={{ display: 'flex', flexDirection: 'column' }}>
+      {defaultChoices.map(renderItem)}
+      {variantChoices.length > 0 && (
+        <MenuItem key="variant-menu" text="Variants" icon="cog">
+          {variantChoices.map(renderItem)}
+        </MenuItem>
+      )}
+    </Menu>
+  );
+};
+
+const chapterRenderer: (isFolderModeEnabled: boolean) => ItemRenderer<SALanguage> =
+  (isFolderModeEnabled: boolean) =>
+  (lang, { handleClick }) => {
+    const isDisabled = isFolderModeEnabled && lang.chapter === Chapter.SOURCE_1;
+    const tooltipContent = isDisabled
+      ? 'Folder mode makes use of lists which are not available in Source 1. To switch to Source 1, disable Folder mode.'
+      : undefined;
+    return (
+      <Tooltip
+        key={lang.displayName}
+        content={tooltipContent}
+        disabled={tooltipContent === undefined}
+      >
+        <MenuItem onClick={handleClick} text={lang.displayName} disabled={isDisabled} />
+      </Tooltip>
+    );
+  };
+
+const ChapterSelectComponent = Select.ofType<SALanguage>();
+
+export const LegacyControlBarChapterSelect: React.FC<ControlBarChapterSelectProps> = ({
+  isFolderModeEnabled,
+  sourceChapter,
+  sourceVariant,
+  handleChapterSelect = () => {},
+  disabled = false
+}) => {
+  const selectedLang = useTypedSelector(store => store.playground.languageConfig.mainLanguage);
+
+  const choices = [
+    ...sourceLanguages,
+    // Full JS/TS version uses eval(), which is a huge security risk, so we only enable
+    // for public deployments. HTML, while sandboxed, is treated the same way to be safe.
+    // See https://github.com/source-academy/frontend/pull/2460#issuecomment-1528759912
+    ...(Constants.playgroundOnly ? [fullJSLanguage, fullTSLanguage, htmlLanguage] : []),
+    ...schemeLanguages,
+    ...pyLanguages,
+    ...javaLanguages
+  ];
+
+  return (
+    <ChapterSelectComponent
+      items={choices.filter(({ mainLanguage }) => mainLanguage === selectedLang)}
+      onItemSelect={handleChapterSelect}
+      itemRenderer={chapterRenderer(isFolderModeEnabled)}
+      itemListRenderer={chapterListRenderer}
+      filterable={false}
+      disabled={disabled}
+    >
+      <Button
+        minimal
+        text={styliseSublanguage(sourceChapter, sourceVariant)}
+        rightIcon={disabled ? null : IconNames.DOUBLE_CARET_VERTICAL}
+        disabled={disabled}
+      />
+    </ChapterSelectComponent>
+  );
+};
diff --git a/src/commons/featureFlags/publicFlags.ts b/src/commons/featureFlags/publicFlags.ts
index d5e23f274e..4e72a3bf5f 100644
--- a/src/commons/featureFlags/publicFlags.ts
+++ b/src/commons/featureFlags/publicFlags.ts
@@ -1,5 +1,10 @@
 import { flagConductorEnable } from '../../features/conductor/flagConductorEnable';
 import { flagConductorEvaluatorUrl } from '../../features/conductor/flagConductorEvaluatorUrl';
+import { flagLanguageDirectoryEnable } from '../../features/languageDirectory/flagLanguageDirectory';
 import { FeatureFlag } from './FeatureFlag';
 
-export const publicFlags: FeatureFlag<any>[] = [flagConductorEnable, flagConductorEvaluatorUrl];
+export const publicFlags: FeatureFlag<any>[] = [
+  flagConductorEnable,
+  flagConductorEvaluatorUrl,
+  flagLanguageDirectoryEnable
+];
diff --git a/src/commons/mocks/StoreMocks.ts b/src/commons/mocks/StoreMocks.ts
index 5bef6dde54..22d8f6c093 100644
--- a/src/commons/mocks/StoreMocks.ts
+++ b/src/commons/mocks/StoreMocks.ts
@@ -6,6 +6,7 @@ import {
   defaultAchievement,
   defaultDashboard,
   defaultFileSystem,
+  defaultLanguageDirectory,
   defaultLeaderboard,
   defaultPlayground,
   defaultRouter,
@@ -36,7 +37,8 @@ export function mockInitialStore(
     featureFlags: defaultFeatureFlags,
     fileSystem: defaultFileSystem,
     sideContent: defaultSideContentManager,
-    vscode: defaultVscode
+    vscode: defaultVscode,
+    languageDirectory: defaultLanguageDirectory
   };
 
   const lodashMergeCustomizer = (objValue: any, srcValue: any) => {
diff --git a/src/commons/navigationBar/subcomponents/LegacyNavigationBarLangSelectButton.tsx b/src/commons/navigationBar/subcomponents/LegacyNavigationBarLangSelectButton.tsx
new file mode 100644
index 0000000000..61159e2b8f
--- /dev/null
+++ b/src/commons/navigationBar/subcomponents/LegacyNavigationBarLangSelectButton.tsx
@@ -0,0 +1,56 @@
+import { Position } from '@blueprintjs/core';
+import { useState } from 'react';
+import { useDispatch } from 'react-redux';
+import {
+  cLanguages,
+  getLanguageConfig,
+  javaLanguages,
+  pyLanguages,
+  SALanguage,
+  schemeLanguages,
+  sourceLanguages,
+  SUPPORTED_LANGUAGES,
+  SupportedLanguage
+} from 'src/commons/application/ApplicationTypes';
+import SimpleDropdown from 'src/commons/SimpleDropdown';
+import { useTypedSelector } from 'src/commons/utils/Hooks';
+import WorkspaceActions from 'src/commons/workspace/WorkspaceActions';
+import { playgroundConfigLanguage } from 'src/features/playground/PlaygroundActions';
+
+const LegacyNavigationBarLangSelectButton = () => {
+  const [isOpen, setIsOpen] = useState(false);
+  const lang = useTypedSelector(store => store.playground.languageConfig.mainLanguage);
+  const dispatch = useDispatch();
+
+  // Legacy default sublanguage mapping
+  const defaultSublanguages: { [lang in SupportedLanguage]: SALanguage } = {
+    [SupportedLanguage.JAVASCRIPT]: sourceLanguages[0],
+    [SupportedLanguage.PYTHON]: pyLanguages[0],
+    [SupportedLanguage.SCHEME]: schemeLanguages[0],
+    [SupportedLanguage.JAVA]: javaLanguages[0],
+    [SupportedLanguage.C]: cLanguages[0]
+  };
+
+  const selectLang = (language: SupportedLanguage) => {
+    const { chapter, variant } = defaultSublanguages[language];
+    dispatch(playgroundConfigLanguage(getLanguageConfig(chapter, variant)));
+    dispatch(WorkspaceActions.chapterSelect(chapter, variant, 'playground'));
+    setIsOpen(false);
+  };
+
+  return (
+    <SimpleDropdown
+      options={SUPPORTED_LANGUAGES.map(l => ({ value: l, label: l }))}
+      onClick={selectLang}
+      selectedValue={lang}
+      popoverProps={{ position: Position.BOTTOM_RIGHT, onClose: () => setIsOpen(false), isOpen }}
+      buttonProps={{
+        rightIcon: 'caret-down',
+        onClick: () => setIsOpen(true),
+        'data-testid': 'NavigationBarLangSelectButton'
+      }}
+    />
+  );
+};
+
+export default LegacyNavigationBarLangSelectButton;
diff --git a/src/commons/navigationBar/subcomponents/NavigationBarLangSelectButton.tsx b/src/commons/navigationBar/subcomponents/NavigationBarLangSelectButton.tsx
index abdc495804..60a69a5d31 100644
--- a/src/commons/navigationBar/subcomponents/NavigationBarLangSelectButton.tsx
+++ b/src/commons/navigationBar/subcomponents/NavigationBarLangSelectButton.tsx
@@ -1,49 +1,48 @@
 import { Position } from '@blueprintjs/core';
-import { useState } from 'react';
+import { useEffect, useState } from 'react';
 import { useDispatch } from 'react-redux';
-import {
-  cLanguages,
-  getLanguageConfig,
-  javaLanguages,
-  pyLanguages,
-  SALanguage,
-  schemeLanguages,
-  sourceLanguages,
-  SUPPORTED_LANGUAGES,
-  SupportedLanguage
-} from 'src/commons/application/ApplicationTypes';
+import { useFeature } from 'src/commons/featureFlags/useFeature';
 import SimpleDropdown from 'src/commons/SimpleDropdown';
 import { useTypedSelector } from 'src/commons/utils/Hooks';
-import WorkspaceActions from 'src/commons/workspace/WorkspaceActions';
-import { playgroundConfigLanguage } from 'src/features/playground/PlaygroundActions';
-
-// TODO: Hardcoded to use the first sublanguage for each language
-const defaultSublanguages: {
-  [lang in SupportedLanguage]: SALanguage;
-} = {
-  [SupportedLanguage.JAVASCRIPT]: sourceLanguages[0],
-  [SupportedLanguage.PYTHON]: pyLanguages[0],
-  [SupportedLanguage.SCHEME]: schemeLanguages[0],
-  [SupportedLanguage.JAVA]: javaLanguages[0],
-  [SupportedLanguage.C]: cLanguages[0]
-};
+import { flagLanguageDirectoryEnable } from 'src/features/languageDirectory/flagLanguageDirectory';
+import LanguageDirectoryActions from 'src/features/languageDirectory/LanguageDirectoryActions';
+
+//TODO <remove legacy>: Remove when conductors.languageDirectory is default behaviour
+import LegacyNavigationBarLangSelectButton from './LegacyNavigationBarLangSelectButton';
+
+function useDirectoryOptions() {
+  const langs = useTypedSelector(s => s.languageDirectory.languages);
+  return langs.map(l => ({ value: l.id, label: l.name }));
+}
 
 const NavigationBarLangSelectButton = () => {
   const [isOpen, setIsOpen] = useState(false);
-  const lang = useTypedSelector(store => store.playground.languageConfig.mainLanguage);
+  const selectedDirLanguageId = useTypedSelector(s => s.languageDirectory.selectedLanguageId);
+
   const dispatch = useDispatch();
-  const selectLang = (language: SupportedLanguage) => {
-    const { chapter, variant } = defaultSublanguages[language];
-    dispatch(playgroundConfigLanguage(getLanguageConfig(chapter, variant)));
-    dispatch(WorkspaceActions.chapterSelect(chapter, variant, 'playground'));
+  const dirOptions = useDirectoryOptions();
+  const languagesLoaded = useTypedSelector(s => s.languageDirectory.languages.length > 0);
+  useEffect(() => {
+    if (!languagesLoaded) {
+      dispatch(LanguageDirectoryActions.fetchLanguages());
+    }
+  }, [languagesLoaded, dispatch]);
+
+  const directoryEnabled = useFeature(flagLanguageDirectoryEnable);
+  if (!directoryEnabled) {
+    return <LegacyNavigationBarLangSelectButton />;
+  }
+
+  const selectDirLanguage = (languageId: string) => {
+    dispatch(LanguageDirectoryActions.setSelectedLanguage(languageId));
     setIsOpen(false);
   };
 
   return (
     <SimpleDropdown
-      options={SUPPORTED_LANGUAGES.map(lang => ({ value: lang, label: lang }))}
-      onClick={selectLang}
-      selectedValue={lang}
+      options={dirOptions}
+      onClick={selectDirLanguage}
+      selectedValue={selectedDirLanguageId ?? undefined}
       popoverProps={{ position: Position.BOTTOM_RIGHT, onClose: () => setIsOpen(false), isOpen }}
       buttonProps={{
         rightIcon: 'caret-down',
diff --git a/src/commons/sagas/LanguageDirectorySaga.ts b/src/commons/sagas/LanguageDirectorySaga.ts
new file mode 100644
index 0000000000..14a13c1a66
--- /dev/null
+++ b/src/commons/sagas/LanguageDirectorySaga.ts
@@ -0,0 +1,66 @@
+import { call, put, select } from 'redux-saga/effects';
+import type { OverallState } from 'src/commons/application/ApplicationTypes';
+import { flagConductorEnable } from 'src/features/conductor/flagConductorEnable';
+import { flagConductorEvaluatorUrl } from 'src/features/conductor/flagConductorEvaluatorUrl';
+import { staticLanguageDirectoryProvider } from 'src/features/languageDirectory/LanguageDirectoryTypes';
+
+import LanguageDirectoryActions from '../../features/languageDirectory/LanguageDirectoryActions';
+import { combineSagaHandlers } from '../redux/utils';
+import { actions } from '../utils/ActionsHelper';
+
+const LanguageDirectorySaga = combineSagaHandlers({
+  [LanguageDirectoryActions.setLanguages.type]: function* () {
+    const state = yield select((s: OverallState) => s.languageDirectory);
+    if (state.selectedLanguageId === null && state.languages.length > 0) {
+      yield put(actions.setSelectedLanguage(state.languages[0].id));
+    }
+    if (state.selectedEvaluatorId === null && state.languages.length > 0) {
+      yield put(actions.setSelectedEvaluator(state.languages[0].evaluators[0].id));
+    }
+  },
+  [LanguageDirectoryActions.fetchLanguages.type]: function* () {
+    const langs = yield call(
+      staticLanguageDirectoryProvider.getLanguages.bind(staticLanguageDirectoryProvider)
+    );
+    yield put(actions.setLanguages(langs));
+  },
+  [LanguageDirectoryActions.setSelectedLanguage.type]: function* (action) {
+    const {
+      payload: { languageId, evaluatorId }
+    } = action;
+    if (evaluatorId) return; // already explicitly set
+    const language = yield call(
+      staticLanguageDirectoryProvider.getLanguageById.bind(staticLanguageDirectoryProvider),
+      languageId
+    );
+    if (!language) return;
+    const defaultEvaluatorId: string | null =
+      language.evaluators.length > 0 ? language.evaluators[0].id : null;
+    if (!defaultEvaluatorId) return;
+    // If state still matches the same language, set evaluator
+    const currentLanguageId: string | null = yield select(
+      (s: OverallState) => s.languageDirectory.selectedLanguageId
+    );
+    if (currentLanguageId !== languageId) return;
+    yield put(actions.setSelectedEvaluator(defaultEvaluatorId));
+  },
+  [LanguageDirectoryActions.setSelectedEvaluator.type]: function* (action) {
+    const {
+      payload: { evaluatorId }
+    } = action;
+    const selectedLanguageId: string | null = yield select(
+      (s: OverallState) => s.languageDirectory.selectedLanguageId
+    );
+    if (!selectedLanguageId) return;
+    const evaluator = yield call(
+      staticLanguageDirectoryProvider.getEvaluatorDefinition.bind(staticLanguageDirectoryProvider),
+      selectedLanguageId,
+      evaluatorId
+    );
+    if (!evaluator) return;
+    yield put(actions.setFlag({ featureFlag: flagConductorEnable, value: true }));
+    yield put(actions.setFlag({ featureFlag: flagConductorEvaluatorUrl, value: evaluator.path }));
+  }
+});
+
+export default LanguageDirectorySaga;
diff --git a/src/commons/sagas/MainSaga.ts b/src/commons/sagas/MainSaga.ts
index f95d60f00e..15fb686c7b 100644
--- a/src/commons/sagas/MainSaga.ts
+++ b/src/commons/sagas/MainSaga.ts
@@ -6,6 +6,7 @@ import Constants from '../utils/Constants';
 import AchievementSaga from './AchievementSaga';
 import BackendSaga from './BackendSaga';
 import GitHubPersistenceSaga from './GitHubPersistenceSaga';
+import LanguageDirectorySaga from './LanguageDirectorySaga';
 import LeaderboardSaga from './LeaderboardSaga';
 import LoginSaga from './LoginSaga';
 import PersistenceSaga from './PersistenceSaga';
@@ -27,6 +28,7 @@ export default function* MainSaga(): SagaIterator {
     fork(GitHubPersistenceSaga),
     fork(RemoteExecutionSaga),
     fork(StoriesSaga),
-    fork(SideContentSaga)
+    fork(SideContentSaga),
+    fork(LanguageDirectorySaga)
   ]);
 }
diff --git a/src/commons/utils/ActionsHelper.ts b/src/commons/utils/ActionsHelper.ts
index 23d5412144..f2114dd5f6 100644
--- a/src/commons/utils/ActionsHelper.ts
+++ b/src/commons/utils/ActionsHelper.ts
@@ -10,6 +10,7 @@ import AchievementActions from '../../features/achievement/AchievementActions';
 import DashboardActions from '../../features/dashboard/DashboardActions';
 import GitHubActions from '../../features/github/GitHubActions';
 import GroundControlActions from '../../features/groundControl/GroundControlActions';
+import LanguageDirectoryActions from '../../features/languageDirectory/LanguageDirectoryActions';
 import LeaderboardActions from '../../features/leaderboard/LeaderboardActions';
 import PersistenceActions from '../../features/persistence/PersistenceActions';
 import PlaygroundActions from '../../features/playground/PlaygroundActions';
@@ -45,7 +46,8 @@ export const actions = {
   ...SideContentActions,
   ...VscodeActions,
   ...SideContentActions,
-  ...FeatureFlagsActions
+  ...FeatureFlagsActions,
+  ...LanguageDirectoryActions
 };
 
 export type SourceActionType = ActionType<typeof actions>;
diff --git a/src/features/languageDirectory/LanguageDirectoryActions.ts b/src/features/languageDirectory/LanguageDirectoryActions.ts
new file mode 100644
index 0000000000..8c9a250572
--- /dev/null
+++ b/src/features/languageDirectory/LanguageDirectoryActions.ts
@@ -0,0 +1,14 @@
+import { createActions } from 'src/commons/redux/utils';
+
+const LanguageDirectoryActions = createActions('conductor/languageDirectory', {
+  /** Fetch languages (saga) */
+  fetchLanguages: null,
+  /** Set languages list */
+  setLanguages: (languages: any[]) => ({ languages }),
+  /** Set selected language; evaluatorId optional (defaults to first available) */
+  setSelectedLanguage: (languageId: string, evaluatorId?: string) => ({ languageId, evaluatorId }),
+  /** Set selected evaluator explicitly */
+  setSelectedEvaluator: (evaluatorId: string) => ({ evaluatorId })
+});
+
+export default LanguageDirectoryActions;
diff --git a/src/features/languageDirectory/LanguageDirectoryReducer.ts b/src/features/languageDirectory/LanguageDirectoryReducer.ts
new file mode 100644
index 0000000000..e9cef78162
--- /dev/null
+++ b/src/features/languageDirectory/LanguageDirectoryReducer.ts
@@ -0,0 +1,22 @@
+import { createReducer, type Reducer } from '@reduxjs/toolkit';
+import { defaultLanguageDirectory } from 'src/commons/application/ApplicationTypes';
+import type { SourceActionType } from 'src/commons/utils/ActionsHelper';
+
+import Actions from './LanguageDirectoryActions';
+import type { LanguageDirectoryState } from './LanguageDirectoryTypes';
+
+export const LanguageDirectoryReducer: Reducer<LanguageDirectoryState, SourceActionType> =
+  createReducer(defaultLanguageDirectory, builder => {
+    builder
+      .addCase(Actions.setLanguages, (state, action) => {
+        state.languages = action.payload.languages as any;
+      })
+      .addCase(Actions.setSelectedLanguage, (state, action) => {
+        const { languageId, evaluatorId } = action.payload;
+        state.selectedLanguageId = languageId;
+        state.selectedEvaluatorId = evaluatorId ?? null;
+      })
+      .addCase(Actions.setSelectedEvaluator, (state, action) => {
+        state.selectedEvaluatorId = action.payload.evaluatorId;
+      });
+  });
diff --git a/src/features/languageDirectory/LanguageDirectoryTypes.ts b/src/features/languageDirectory/LanguageDirectoryTypes.ts
new file mode 100644
index 0000000000..d19bf23d9b
--- /dev/null
+++ b/src/features/languageDirectory/LanguageDirectoryTypes.ts
@@ -0,0 +1,45 @@
+import {
+  getEvaluatorDefinition,
+  IEvaluatorDefinition,
+  ILanguageDefinition,
+  languageMap,
+  languages
+} from '@sourceacademy/language-directory';
+
+export type LanguageDirectoryState = {
+  readonly selectedLanguageId: string | null;
+  readonly selectedEvaluatorId: string | null;
+  readonly languages: ILanguageDefinition[];
+};
+
+export interface LanguageDirectoryProvider {
+  getLanguages(): Promise<ILanguageDefinition[]>;
+  getLanguageById(languageId: string): Promise<ILanguageDefinition | undefined>;
+  getEvaluatorDefinition(
+    languageId: string,
+    evaluatorId: string
+  ): Promise<IEvaluatorDefinition | undefined>;
+}
+
+export class StaticLanguageDirectoryProvider implements LanguageDirectoryProvider {
+  async getLanguages(): Promise<ILanguageDefinition[]> {
+    return languages;
+  }
+
+  async getLanguageById(languageId: string): Promise<ILanguageDefinition | undefined> {
+    return languageMap.get(languageId);
+  }
+
+  async getEvaluatorDefinition(
+    languageId: string,
+    evaluatorId: string
+  ): Promise<IEvaluatorDefinition | undefined> {
+    const language = languageMap.get(languageId);
+    if (!language) return undefined;
+    return getEvaluatorDefinition(language, evaluatorId);
+  }
+}
+
+export const staticLanguageDirectoryProvider = new StaticLanguageDirectoryProvider();
+
+export type { ILanguageDefinition, IEvaluatorDefinition };
diff --git a/src/features/languageDirectory/flagLanguageDirectory.ts b/src/features/languageDirectory/flagLanguageDirectory.ts
new file mode 100644
index 0000000000..07614141a0
--- /dev/null
+++ b/src/features/languageDirectory/flagLanguageDirectory.ts
@@ -0,0 +1,10 @@
+import { createFeatureFlag } from '../../commons/featureFlags';
+import { featureSelector } from '../../commons/featureFlags/featureSelector';
+
+export const flagLanguageDirectoryEnable = createFeatureFlag(
+  'conductor.language.directory',
+  false,
+  'Enable new language directory powered selection UI and runtime selection.'
+);
+
+export const selectLanguageDirectoryEnable = featureSelector(flagLanguageDirectoryEnable);
diff --git a/yarn.lock b/yarn.lock
index bea5428841..d0f6db68a4 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3335,6 +3335,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@sourceacademy/language-directory@https://github.com/loyaltypollution/language-directory.git#866cc934372a19e514af0025947ce7f1f5a6e1fc":
+  version: 0.0.2
+  resolution: "@sourceacademy/language-directory@https://github.com/loyaltypollution/language-directory.git#commit=866cc934372a19e514af0025947ce7f1f5a6e1fc"
+  checksum: 10c0/a6267cc71585f2cd09b53d416477e18fd2172eb42ca208350cb6aa4cec20fee56580a40cf29a40acd03c8321d6171694473cceb0d1e1b2c7e32dc62569104752
+  languageName: node
+  linkType: hard
+
 "@sourceacademy/sharedb-ace@npm:2.1.1":
   version: 2.1.1
   resolution: "@sourceacademy/sharedb-ace@npm:2.1.1"
@@ -7620,6 +7627,7 @@ __metadata:
     "@rsbuild/plugin-svgr": "npm:^1.2.0"
     "@sentry/react": "npm:^10.5.0"
     "@sourceacademy/c-slang": "npm:^1.0.21"
+    "@sourceacademy/language-directory": "https://github.com/loyaltypollution/language-directory.git#866cc934372a19e514af0025947ce7f1f5a6e1fc"
     "@sourceacademy/sharedb-ace": "npm:2.1.1"
     "@sourceacademy/sling-client": "npm:^0.1.0"
     "@svgr/webpack": "npm:^8.0.0"
@@ -7688,7 +7696,6 @@ __metadata:
     js-yaml: "npm:^4.1.0"
     jsdom: "npm:^26.0.0"
     konva: "npm:^9.2.0"
-    language-directory: "https://github.com/source-academy/language-directory.git"
     lodash: "npm:^4.17.21"
     lz-string: "npm:^1.4.4"
     mdast-util-from-markdown: "npm:^2.0.0"
@@ -9367,13 +9374,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"language-directory@https://github.com/source-academy/language-directory.git":
-  version: 0.0.1
-  resolution: "language-directory@https://github.com/source-academy/language-directory.git#commit=8e406e4b28a7df5e3e66fdf3005092d0cf861143"
-  checksum: 10c0/2db1dd6a94497232e2a183f10769f9e98658636ad3c0c56ae2d54abd5a414dcfbaa994e651ac94507d129147da523254d81103a75f5e0ad2cbaf2274ee3f146d
-  languageName: node
-  linkType: hard
-
 "lcov-parse@npm:^1.0.0":
   version: 1.0.0
   resolution: "lcov-parse@npm:1.0.0"