| // Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| // @dart = 2.9 |
| |
| /// @assertion We extend the list grammar to allow spread elements in addition to |
| /// regular elements: |
| /// listLiteral: |
| /// const? typeArguments? '[' spreadableList? ']' |
| /// ; |
| /// |
| /// spreadableList: |
| /// spreadableExpression ( ',' spreadableExpression )* ','? |
| /// ; |
| /// |
| /// spreadableExpression: |
| /// expression | |
| /// spread |
| /// ; |
| /// |
| /// spread: |
| /// ( '...' | '...?' ) expression |
| /// ; |
| /// |
| /// Instead of [expressionList], this uses a new [spreadableList] rule since |
| /// [expressionList] is used elsewhere in the grammar where spreads aren't |
| /// allowed. Each element in a list is either a normal expression or a spread |
| /// element. If the spread element starts with [...?], it's a null-aware spread |
| /// element. |
| /// @description Checks that [spreadableList] can not be declared as constant if |
| /// spreadable element is not a constant. |
| /// @author iarkh@unipro.ru |
| |
| |
| main() { |
| List list1 = ["abc", "int", "hello"]; |
| List list2; |
| int i; |
| |
| List a = const [...list2]; //# 01: compile-time error |
| a = const ["testme", ...list2]; //# 02: compile-time error |
| a = const [...list2, "testme"]; //# 03: compile-time error |
| a = const ["abc", ...list1, "int", "hello", 1, ...list2, 2, 12]; //# 04: compile-time error |
| a = const [...list1, i]; //# 05: compile-time error |
| } |