| // Copyright 2013 The Flutter Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| /// A utility method for comparing lists for equality. |
| /// |
| /// This method assumes that [T] implements a meaningful equality operator. |
| /// Therefore, thi method should not be used to compare lists containing |
| /// nested lists. |
| bool listEquals<T>(List<T>? a, List<T>? b) { |
| if (a == null) { |
| return b == null; |
| } |
| if (b == null || a.length != b.length) { |
| return false; |
| } |
| if (identical(a, b)) { |
| return true; |
| } |
| for (int index = 0; index < a.length; index += 1) { |
| if (a[index] != b[index]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /// Linearly interpolates between two doubles by factor t. |
| @pragma('vm:prefer-inline') |
| double lerpDouble(double a, double b, double t) { |
| assert(a.isFinite); |
| assert(b.isFinite); |
| assert(t <= 1.0); |
| assert(t >= 0.0); |
| return (1 - t) * a + t * b; |
| } |
