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// 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.
/// @assertion Dynamic Semantics
/// The new dynamic semantics are a superset of the original behavior. To avoid
/// redundancy and handle nested uses, the semantics are expressed in terms of a
/// separate procedure below:
/// Lists
/// 1. Create a fresh instance [collection] of a class that implements [List<E>].
/// An implementation is, of course, free to optimize by pre-allocating a list
/// of the correct capacity when its size is statically known. Note that when
/// [if] and [for] come into play, it's no longer always possible to
/// statically tell the final size of the resulting flattened list.
/// 2. For each [element] in the list literal:
/// i. Evaluate [element] using the procedure below.
/// 3. The result of the literal expression is [collection].
/// . . .
/// To evaluate a collection [element]:
/// This procedure handles elements in both list and map literals because the
/// only difference is how a base expression element or entry element is handled.
/// The control flow parts are the same so are unified here.
/// 2. Else, if [element] is a synchronous [for-in] element:
/// i. Evaluate the iterator expression to a value [sequence].
/// ii. Evaluate [sequence.iterator] to a value [iterator].
/// iii. Loop:
/// a. If the boolean conversion of [iterator.moveNext()] does not
/// return [true], exit the loop.
/// b. If the [for-in] element declares a variable, create a fresh
/// [variable] for it. Otherwise, use the existing [variable] it
/// refers to.
/// c. Evaluate [iterator.current] and bind it to [variable].
/// d. Evaluate the body element using this procedure in the scope of
/// [variable].
/// iv. If the [for-in] element declares a variable, discard it.
/// . . .
/// @description Checks that if [element] of list literal is a synchronous
/// [for-in] element, this element is evaluated using the specified procedure.
/// @author
import "../../Utils/expect.dart";
main() {
var l1 = [1, 2];
var l2 = [3, 4, 5];
var list1exp = <int>[];
var n0 = l1.iterator;
while (n0.moveNext()) {
var id = n0.current;
n0 = l2.iterator;
while (n0.moveNext()) {
var id = n0.current;
list1exp.add(id + 1);
Expect.isTrue(list1exp is List<int>);
var list1 = <int>[for (var v in l1) v, for (var v in l2) v + 1];
// list1exp [1, 2, 4, 5, 6]
Expect.isTrue(list1 is List<int>);
Expect.listEquals(list1exp, list1);