moulo

vm/vm.go

@@ -112,7 +112,7 @@ func (vm *VM) Run() error {
 				return err
 			}
 
-		case code.OpAdd, code.OpSub, code.OpMul, code.OpDiv:
+		case code.OpAdd, code.OpSub, code.OpMul, code.OpDiv, code.OpMod:
 			err := vm.executeBinaryOperation(op)
 			if err != nil {
 				return err
@@ -543,6 +543,9 @@ func (vm *VM) executeBinaryIntegerOperation(op code.Opcode, left, right object.O
 		result = leftValue * rightValue
 	case code.OpDiv:
 		result = leftValue / rightValue
+	case code.OpMod:
+		result = leftValue % rightValue
+
 	default:
 		return fmt.Errorf("unknown integer operator: %d", op)
 	}

vm/vm_test.go

@@ -224,6 +224,7 @@ func TestIntegerArithmetic(t *testing.T) {
 		{"-10", -10},
 		{"-50 + 100 + -50", 0},
 		{"(5 + 10 * 2 + 15 / 3) * 2 + -10", 50},
+		{"5 % 2", 1},
 	}
 
 	runVmTests(t, tests)