A handy function for filtering any iterable and objects in javascript.
$ yarn add filter-it
# or
$ npm i -S filter-itThe api is straight forward and oriented on Array.prototype.filter.
const newIterable = filter(iterable, callback);
The iterable or object to filter. Supported types are String, Array, TypedArray, Map, Set, (any Iterable) & Object.
A function to test every element or value of the iterable. The current item will be preserved when the callback returns a truthy value.
The function takes 3 parameters:
- value: The current element being processed.
- key: The corresponding key
- iterable: The iterable passed to filter
filter() returns a new instance of the iterable with only the entries passed the callback.
filter("a1b2c3d4e5", char => char >= "0" && char <= "9"); // => "12345" filter(new String("a1b2c3d4e5"), (char, index) => index & 1); // => [String: '12345']
const map = new Map([['a', 1], ['b', 2], ['c', 3], ['d', 4], ['e', 5]]); filter(map, (value, key) => key === 'b' || value & 1); // => Map { 'a' => 1, 'b' => 2, 'c' => 3, 'e' => 5 }
const set = new Set(['a', 1, 'b', 2, 'c', 3]); filter(set, (value, key) => value === key && typeof value === 'string'); // => Set { 'a', 'b', 'c' }
const arr = ['a', 1, 'b', 2, 'c', 3]; filter(arr, (value, index) => index & 1); // => [ '1', '2', '3' ]
const typedArr = new Int32Array([1, 2, -3, -4, 5]); filter(typedArr, i => i < 0); // => Int32Array [ -3, -4 ]
const obj = { a: 1, b: 2, c: 3, d: 4, e: 5 }; filter(obj, (value, key) => key === 'b' || value & 1); // => { a: 1, b: 2, c: 3, e: 5 }