fixed mutability

compiler/compiler.go

@@ -210,13 +210,11 @@ func (c *Compiler) Compile(node ast.Node) error {
 		}
 
 		if symbol.Scope == GlobalScope {
-			c.emit(code.OpGetGlobal, symbol.Index)
+			c.emit(code.OpAssignGlobal, symbol.Index)
 		} else {
-			c.emit(code.OpGetLocal, symbol.Index)
+			c.emit(code.OpAssignLocal, symbol.Index)
 		}
 
-		c.emit(code.OpAssign)
-
 	case *ast.LetStatement:
 		symbol, ok := c.symbolTable.Resolve(node.Name.Value)
 		if !ok {

compiler/compiler_test.go

@@ -779,8 +779,7 @@ func TestAssignmentStatementScopes(t *testing.T) {
 				55,
 				[]code.Instructions{
 					code.Make(code.OpConstant, 1),
-					code.Make(code.OpGetGlobal, 0),
-					code.Make(code.OpAssign),
+					code.Make(code.OpAssignGlobal, 0),
 					code.Make(code.OpReturn),
 				},
 			},
@@ -791,48 +790,19 @@ func TestAssignmentStatementScopes(t *testing.T) {
 				code.Make(code.OpPop),
 			},
 		},
-
 		{
 			input: `
-			            fn() {
-			                let num = 55;
-			                num
-			            }
-			            `,
+            fn() { let num = 0; num  = 55; }
+            `,
 			expectedConstants: []interface{}{
+				0,
 				55,
-				[]code.Instructions{
-					code.Make(code.OpConstant, 0),
-					code.Make(code.OpSetLocal, 0),
-					code.Make(code.OpGetLocal, 0),
-					code.Make(code.OpReturnValue),
-				},
-			},
-			expectedInstructions: []code.Instructions{
-				code.Make(code.OpClosure, 1, 0),
-				code.Make(code.OpPop),
-			},
-		},
-		{
-			input: `
-			            fn() {
-			                let a = 55;
-			                let b = 77;
-			                a + b
-			            }
-			            `,
-			expectedConstants: []interface{}{
-				55,
-				77,
 				[]code.Instructions{
 					code.Make(code.OpConstant, 0),
 					code.Make(code.OpSetLocal, 0),
 					code.Make(code.OpConstant, 1),
-					code.Make(code.OpSetLocal, 1),
-					code.Make(code.OpGetLocal, 0),
-					code.Make(code.OpGetLocal, 1),
-					code.Make(code.OpAdd),
-					code.Make(code.OpReturnValue),
+					code.Make(code.OpAssignLocal, 0),
+					code.Make(code.OpReturn),
 				},
 			},
 			expectedInstructions: []code.Instructions{
@@ -840,24 +810,6 @@ func TestAssignmentStatementScopes(t *testing.T) {
 				code.Make(code.OpPop),
 			},
 		},
-		{
-			input: `
-						let a = 0;
-						let a = a + 1;
-						`,
-			expectedConstants: []interface{}{
-				0,
-				1,
-			},
-			expectedInstructions: []code.Instructions{
-				code.Make(code.OpConstant, 0),
-				code.Make(code.OpSetGlobal, 0),
-				code.Make(code.OpGetGlobal, 0),
-				code.Make(code.OpConstant, 1),
-				code.Make(code.OpAdd),
-				code.Make(code.OpSetGlobal, 0),
-			},
-		},
 	}
 
 	runCompilerTests(t, tests)