adding while

ibeckermayer · Mar 13, 2021 · e524499 · e524499
1 parent cf5f23c
commit e524499
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Showing 2 changed files with 49 additions and 2 deletions.
diff --git a/Compiler/pkg/compiler/compilationengine.go b/Compiler/pkg/compiler/compilationengine.go
@@ -712,8 +712,55 @@ func (ce *CompilationEngine) compileLet() error {
 }
 
 // 'while '(' expression ')' '{' statements '}'
+// eats its own final token before returning, so calling function can expect to already be on the next token
 func (ce *CompilationEngine) compileWhile() error {
-	panic("not implemented") // TODO: Implement
+	ce.openXMLTag("whileStatement")
+	defer ce.closeXMLTag("whileStatement")
+
+	if err := ce.compileKeyword("while"); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.advance(); err != nil {
+		return SyntaxError(err)
+	}
+	if err := ce.compileSymbol("("); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.advance(); err != nil {
+		return SyntaxError(err)
+	}
+	if err := ce.compileExpression(); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.compileSymbol(")"); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.advance(); err != nil {
+		return SyntaxError(err)
+	}
+	if err := ce.compileSymbol("{"); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.advance(); err != nil {
+		return SyntaxError(err)
+	}
+	if err := ce.compileStatements(); err != nil {
+		return SyntaxError(err)
+	}
+
+	if err := ce.compileSymbol("}"); err != nil {
+		return SyntaxError(err)
+	}
+	if err := ce.advance(); err != nil {
+		return SyntaxError(err)
+	}
+
+	return nil
 }
 
 // 'return' expression? ';'

diff --git a/Compiler/test/ExpressionLessSquare/SquareGame.xml b/Compiler/test/ExpressionLessSquare/SquareGame.xml
@@ -528,4 +528,4 @@
     </subroutineBody>
   </subroutineDec>
   <symbol> } </symbol>
-</class>
+</class>