| // Copyright (c) 2013, 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 T fold<T>(T initialValue, T combine(previousValue, E element)) |
| /// Reduces a collection to a single value by iteratively combining each |
| /// element of the collection with an existing value using. |
| /// Uses initialValue as the initial value, then iterates through the elements |
| /// and updates the value with each element using the combine function. |
| /// @description Checks that the returned value is correct. |
| /// @author msyabro |
| |
| |
| import "dart:typed_data"; |
| import "../../../Utils/expect.dart"; |
| |
| checkInt(List<double> list, double expected) { |
| var l = new Float64List.fromList(list); |
| var res = l.fold(0, (num prev, double cur) => prev + cur); |
| Expect.equals(expected, res); |
| } |
| |
| checkString(List<double> list, String expected) { |
| var l = new Float64List.fromList(list); |
| var res = l.fold("", (prev, cur) => "${prev}${cur}"); |
| Expect.equals(expected, res); |
| } |
| |
| checkConst(List<double> list, int expected) { |
| var l = new Float64List.fromList(list); |
| var res = l.fold(0, (prev, cur) => 1); |
| Expect.equals(expected, res); |
| } |
| |
| |
| main() { |
| checkInt([], 0.0); |
| checkInt([1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0], 55.0); |
| checkInt([10.0, -1.0, -2.0, -3.0, -4.0], 0.0); |
| |
| checkString([], ""); |
| checkString([1.1], "1.1"); |
| checkString([1.1, 2.1, 3.1, 4.1, 5.1], "1.12.13.14.15.1"); |
| |
| checkConst([], 0); |
| checkConst([1.0, 2.0, 3.0], 1); |
| } |