list_ext #

Dart extension method for Iterable and List.

Usage #

To use this plugin, add list_ext as a dependency in your pubspec.yaml file.

Than add import 'package:list_ext/list_ext.dart'; to the file for use extension methods.

Example #

import 'package:list_ext/list_ext.dart';

void main() {
  final list = [1, 2, 5];
  final sum = list.sum();
  print('Sum: $sum');
  // Output: Sum: 8
}

Methods classifier #

Common #

• countWhere() - returns count of elements that satisfy the predicate.
• containsWhere() - returns true if the collection contains an element that satisfy the predicate.
• containsAll() - returns true if the collection contains all elements from the given collection.

Equality

• isNullOrEmpty/isNotNullOrEmpty - check for null or empty.
• isUnorderedEquivalent() - check equality of the elements of two iterables without considering order.

Search

• firstWhereOrNull() - return the first found element or null if no element found.

Safe elements access

• firstOrNull - returns the first element or null if collection is empty.
• tryElementAt() - returns the element at the index if exists or orElse if it is out of range.

Transformation #

• reduceValue() - reduces values of elements in a collection to a single value by iteratively combining its using the provided function.

Iterables

• chunks() - splits into chunks of the specified size.

String

• joinOf() - get string value for each element and concatenates it with passed separator.

Map

• toMap() - creates a Map instance from the iterable.

Math #

• maxOf() - return max of values by elements.
• minOf() - return min of values by elements.
• sumOf()/sumOfDouble() - returns sum of values by elements.
• avgOf()/avgOfDouble() - returns the average value of values by elements.

There are specific version of methods for Iterables of num (int and double):

• max().
• min().
• sum().
• avg().

List specific methods #

Transformation #

List

• copyWith() - Copy current list with adding element.
• copyWithAll() - Copy current list with adding all elements from another list.