Some minor formatting/cosmetic/textual changes

Author: shesek

src/error.rs

@@ -235,7 +235,7 @@ pub enum RuntimeError {
     #[error("Invalid secret key length {0} (expected 32 for single key or 78 for xpub)")]
     InvalidSecKeyLen(usize),
 
-    #[error("Invalid tr() use. Valid invocations are tr(PubKey), tr(Policy|Array<Policy>), tr(PubKey, Policy|Array<Policy>), tr(PubKey, Script|Array<Script>) or tr(PubKey, Hash)")]
+    #[error("Invalid tr() use. Valid invocations are tr(PubKey), tr(Policy|Array<Policy>), tr(PubKey, Policy|Array<Policy>), tr(Script|Array<Script>), tr(PubKey, Script|Array<Script>) or tr(PubKey, Hash merkle_root)")]
     TaprootInvalidTrUse,
 
     #[error("Invalid Taproot unspendable key: {}", ValErrFmt(.0))]

src/playground.rs

@@ -118,8 +118,8 @@ lazy_static! {
         // or a welcome message if there aren't any.
         dyn fn main() = symbol({
             $env = str(env::pretty());
-            if !isEmpty($env) then "// Environment variables:\n\n" + $env
-            else "// Welcome! Put some variables in your environment and they will show up here."
+            if !isEmpty($env) then "// Defined variables:\n\n" + $env
+            else "// Welcome! Put some variables in your environment and they will show up here, or set a final return value."
         });
 
         // Wrap some String-returning functions to return a Symbol instead, to have them displayed in

src/stdlib/btc.minsc

@@ -58,19 +58,47 @@ fn tx::sighash::tr_leaf($tx, $vin, $script_leaf, $utxos, $sighash_ty) = psbt::si
 
 // TOOD tx::sighash::sw0() with just the signed utxo & tx::sighash::presw() with just the utxo's script
 
+//
+// Script Looping utilities
+//
+
+// Loop unrolling: run $loop_body as long as $condition is met, up to $max_iterations times.
+// $loop_body can be a Script or a Function that accepts the iteration count and returns a Script.
+// For example: `<num> unrollLoop(50, `OP_DUP 0 OP_GREATERTHANOREQUAL`, `OP_1SUB`)` to count down from <num> to 0, for <num>s of up to 50
+// more advanced example with some comments: https://min.sc/v0.3/#gist=758c25489869d77d4ef624ea43f18c49
+fn unrollLoop($max_iterations, $condition, $loop_body) {
+  $body_fn = if isFunction($loop_body) then $loop_body else |_| $loop_body;
+
+  fn _unrollLoop($i) =
+    if $i < $max_iterations then `$condition OP_IF $body_fn($i) _unrollLoop($i+1) OP_ENDIF`
+    else `$condition OP_NOT OP_VERIFY` // fail the script if the condition is still met after $max_iterations
+  ;
+  _unrollLoop(0)
+}
+
+// Read the top stack item as the number of times to run $for_body
+// Example with accumulator: `0 <num> unrollFor(50, `OP_DUP OP_ROT OP_ADD OP_SWAP`)` to sum the numbers from <num> to 1
+fn unrollFor($max_iterations, $for_body) {
+  $body_fn = if isFunction($for_body) then $for_body else |_| $for_body;
+  `
+    unrollLoop($max_iterations, `OP_DUP OP_0NOTEQUAL`, |$i| `$body_fn($i) OP_1SUB`)
+    OP_DROP // drop the counter (always 0 by now)
+  `
+}
+
 //
 // Script Altstack manipulation
 //
 
 // ROLL/PICK from the altstack, for static $n
 fn rollAlt($n) = `
   OP_FROMALTSTACK*$n
-  {`OP_SWAP OP_TOALTSTACK`*($n - 1)}
+  {`OP_SWAP OP_TOALTSTACK`*($n-1)}
 `;
 fn pickAlt($n) = `
   OP_FROMALTSTACK*$n
   OP_DUP OP_TOALTSTACK
-  {`OP_SWAP OP_TOALTSTACK`*($n - 1)}
+  {`OP_SWAP OP_TOALTSTACK`*($n-1)}
 `;
 
 // ROLL/PICK from the altstack, using the number at the top of the stack as the depth
@@ -107,34 +135,6 @@ fn nFromAlt($max_n) = `
   unrollFor($max_n, `OP_FROMALTSTACK OP_ROT*2`)
 `;
 
-//
-// Script Looping utilities
-//
-
-// Loop unrolling: run $loop_body as long as $condition is met, up to $max_iterations times
-// $loop_body can be a Script or a Function that accepts the iteration count and returns a Script.
-// For example: `<num> unrollLoop(50, `OP_DUP 0 OP_GREATERTHANOREQUAL`, `OP_1SUB`)` to count down from <num> to 0, for <num>s of up to 50
-// more advanced example with some comments: https://min.sc/v0.3/#gist=758c25489869d77d4ef624ea43f18c49
-fn unrollLoop($max_iterations, $condition, $loop_body) {
-  $body_fn = if isFunction($loop_body) then $loop_body else |_| $loop_body;
-
-  fn _unrollLoop($i) =
-    if $i < $max_iterations then `$condition OP_IF $body_fn($i) _unrollLoop($i+1) OP_ENDIF`
-    else `$condition OP_NOT OP_VERIFY` // fail the script if the condition is still met after $max_iterations
-  ;
-  _unrollLoop(0)
-}
-
-// Read the top stack item as the number of times to run $for_body
-// Example with accumulator: `0 <num> unrollFor(50, `OP_DUP OP_ROT OP_ADD OP_SWAP`)` to sum the numbers from <num> to 1
-fn unrollFor($max_iterations, $for_body) {
-  $body_fn = if isFunction($for_body) then $for_body else |_| $for_body;
-  `
-    unrollLoop($max_iterations, `OP_DUP OP_0NOTEQUAL`, |$i| `$body_fn($i) OP_1SUB`)
-    OP_DROP // drop the counter (always 0 by now)
-  `
-}
-
 //
 // Script Conditional control structures
 //
@@ -200,14 +200,14 @@ fn select($scripts) =
 //
 
 MARK_SCRIPT=true;
-MARK_CTX="";
+MARK_CTX=[];
 // SCRIPT_MARKER_MAGIC available from Rust
 
 dyn fn mark($kind, $body) = if !MARK_SCRIPT then `` else
-  `SCRIPT_MARKER_MAGIC OP_DROP $kind OP_DROP {MARK_CTX+str($body)} OP_DROP`;
-dyn fn mark::comment($comment) = mark("comment", $comment);
-dyn fn mark::label($name) = mark("label", $name);
+  `SCRIPT_MARKER_MAGIC OP_DROP $kind OP_DROP str($body) OP_DROP`;
+dyn fn mark::comment($comment) = mark("comment", join(MARK_CTX+[str($comment)], " · "));
+dyn fn mark::label($name) = mark("label", join(MARK_CTX+[str($name)], "__"));
 dyn fn mark::ctx($$context, $$fn) {
-  MARK_CTX = MARK_CTX + $$context;
+  MARK_CTX = MARK_CTX + [ str($$context) ];
   $$fn()
 }

src/stdlib/btc.rs

@@ -511,10 +511,10 @@ pub fn fmt_script<W: fmt::Write>(
         }
         ScriptFmt::Minsc(false) => (),
         ScriptFmt::ScriptWiz => {
-            writeln!(f, "// ScriptWiz formatted")?;
+            writeln!(f, "// ScriptWiz formatted\n")?;
         }
         ScriptFmt::BitIde => {
-            writeln!(f, "// BitIDE formatted")?;
+            writeln!(f, "// BitIDE formatted\n")?;
         }
     }
 

src/stdlib/keys.rs

@@ -139,7 +139,7 @@ pub mod fns {
         .into())
     }
 
-    /// Convert a multi-PubKey/SecKey/Descriptor into an array of singles
+    /// Convert a multi-path PubKey/SecKey/Descriptor into an array of singles
     ///
     /// singles(PubKey<Multi>|SecKey<Multi>|Descriptor<Multi>) -> Array<PubKey|SecKey|Descriptor>
     pub fn singles(args: Array, _: &ScopeRef) -> Result<Value> {