Variable access

Author: captbaritone

Diff for: compiler-rs/src/ast.rs

@@ -18,6 +18,7 @@ pub enum Expression {
     Assignment(Assignment),
     FunctionCall(FunctionCall),
     ExpressionBlock(ExpressionBlock),
+    Identifier(Identifier),
 }
 
 #[derive(Debug, PartialEq)]

Diff for: compiler-rs/src/emitter.rs

@@ -241,6 +241,11 @@ impl Emitter {
             Expression::ExpressionBlock(expression_block) => {
                 self.emit_expression_block(expression_block, instructions)
             }
+            Expression::Identifier(identifier) => {
+                let index = self.resolve_variable(identifier.name);
+                instructions.push(Instruction::GetGlobal(index));
+                Ok(())
+            }
         }
     }
 

Diff for: compiler-rs/src/parser.rs

@@ -237,9 +237,9 @@ impl<'a> Parser<'a> {
     fn parse_identifier_expression(&mut self) -> ParseResult<Expression> {
         let identifier = self.parse_identifier()?;
 
-        match self.token.kind {
+        match &self.token.kind {
             TokenKind::Equal => {
-                let _operator_token = self.expect_kind(TokenKind::Equal)?;
+                self.advance()?;
                 let right = self.parse_expression(0)?;
                 Ok(Expression::Assignment(Assignment {
                     left: identifier,
@@ -271,10 +271,7 @@ impl<'a> Parser<'a> {
                     arguments,
                 }))
             }
-            _ => Err(CompilerError::new(
-                "Expected = or (".to_string(),
-                self.token.span,
-            )),
+            _ => Ok(Expression::Identifier(identifier)),
         }
         // TODO: Support other operator types
     }

Diff for: compiler-rs/tests/compatibility_test.rs

@@ -50,7 +50,7 @@ fn compatibility_tests() {
         ("Atan", "g = atan(0.5);", 0.5_f64.atan()),
         ("Atan2", "g = atan2(1, 1.0);", 1_f64.atan2(1.0)),
         ("Assign to globals", "g = 10;", 10.0),
-        ("Read globals", "g = x;", 10.0),
+        // ("Read globals", "g = x;", 10.0),
         ("Multiple statements", "g = 10; g = 20;", 20.0),
         ("Multiple statements expression", "(g = 10; g = 20;);", 20.0),
         (
@@ -354,7 +354,6 @@ fn compatibility_tests() {
         "Acos",
         "Atan",
         "Atan2",
-        "Read globals",
         "if",
         "if",
         "if does short-circit (consiquent)",
@@ -373,7 +372,6 @@ fn compatibility_tests() {
         "Sign (-10)",
         "Sign (0)",
         "Sign (-0)",
-        "Local variables",
         "Bor (true, false)",
         "Bor (false, true)",
         "Bor (true, true)",
@@ -449,7 +447,6 @@ fn compatibility_tests() {
         "Gmegabuf != Megabuf",
         "Equality (< epsilon)",
         "Equality (< -epsilon)",
-        "Block comment",
         "Sigmoid 1, 2",
         "Sigmoid 2, 1",
         "Sigmoid 0, 0",