compiler: Equality comparison operator compilation error message

ArhanChaudhary · Apr 19, 2024 · f90f179 · f90f179
1 parent c0b4d8e
commit f90f179
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diff --git a/TODO.md b/TODO.md
@@ -4,7 +4,6 @@
  * divide the Jack tutorial into more subsections
  * arguments keyword in docs (nArgs doesnt matter)
 
- * ub: abs -32768, stack overflows, operator priority modifying stack frame, modifying registers, < and >, too few arguments (mention it is a wontfix)
  * hardware limitations
  * max ROM 32768 and max static 240 and max stack 1792 and screen stuff and multi keyboard input
 

diff --git a/src/compiler/engine.ts b/src/compiler/engine.ts
@@ -703,7 +703,12 @@ export default class Engine {
  this.compileTerm();
  const op = this.tokenizer.token() as SymbolToken;
  if (OPS.includes(op)) {
+ const currentIsEquals = op === SymbolToken.EQUAL;
  this.tokenizer.advance();
+ const nextIsEquals = this.tokenizer.token() === SymbolToken.EQUAL;
+ if (currentIsEquals && nextIsEquals) {
+ throw this.tokenizer.syntaxError("", "use '=' instead of '==' for the equality comparison");
+ }
  this.compileExpression();
  this.vmwriter.writeArithmetic(op);
  }