Overview

This is a simple Dart package that provides fast and secure equality comparison as a mixin. This provides great compatibility to exsiting code.

It optionally offers hash caching to improve the speed of e.g. Map's and Set's significantly.

By default the widely spread Jenkins hash function is used, but you are free to also implement and provide your own hash engine, suiting your needs.

Objects of any kind are allowed into hashParameters. Simple types and the standard collections like List, Iterable, Map an Set are supported by default. When you use own classes make sure to use the FastEquatable mixin as well, or make sure at least hashCode and operator == are overriden.

Example

class FastEquatableCached with FastEquatable {
  final String value1;
  final List<String>? value2;

  FastEquatableCached(this.value1, this.value2);

  @override
  //This is a immutable object, so we want to cache the hash
  bool get cacheHash => true;

  @override
  List<Object?> get hashParameters => [value1, value2];
}

Benchmark

In the example you will find a benchmark code, showing off the resulting speed improvement.

equatable for 1000000 elements(RunTime): 8583044.5 us.
fast_equatable (uncached) for 1000000 elements(RunTime): 8493327.5 us.
fast_equatable (cached) for 1000000 elements(RunTime): 3329455.5 us.