https://github.com/alrik/filter-iterable-javascript

A javascript lib for filtering any iterable or plain object with a simple, convenient api.
https://github.com/alrik/filter-iterable-javascript

array-filter filter iterable javascript js map map-filter object object-filter set set-filter string-filter

Last synced: 21 days ago
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A javascript lib for filtering any iterable or plain object with a simple, convenient api.

• Host: GitHub
• URL: https://github.com/alrik/filter-iterable-javascript
• Owner: alrik
• Created: 2018-02-08T21:57:47.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2018-02-08T23:47:04.000Z (almost 7 years ago)
• Last Synced: 2024-12-02T20:18:44.908Z (about 1 month ago)
• Topics: array-filter, filter, iterable, javascript, js, map, map-filter, object, object-filter, set, set-filter, string-filter
• Language: JavaScript
• Size: 4.88 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
# filter-iterable-javascript

A handy function for filtering any iterable and objects in javascript.

## Installation

```bash

$ yarn add filter-it

# or

$ npm i -S filter-it

```

## Usage

The api is straight forward and oriented on [Array.prototype.filter](https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/Global_Objects/Array/filter).

```js

const newIterable = filter(iterable, callback);

```

### Parameters

#### iterable

The iterable or object to filter.

Supported types are String, Array, TypedArray, Map, Set, (any Iterable) & Object.

#### callback

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

### Return Value

`filter()` returns a new instance of the iterable with only the entries passed the callback.

### Examples

#### Filtering strings

```js

filter("a1b2c3d4e5", char => char >= "0" && char <= "9"); 

// => "12345"

filter(new String("a1b2c3d4e5"), (char, index) => index & 1); 

// => [String: '12345']

```

#### Filtering maps

```js

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 } 

```

#### Filtering sets

```js

const set = new Set(['a', 1, 'b', 2, 'c', 3]);

filter(set, (value, key) => value === key && typeof value === 'string'); 

// => Set { 'a', 'b', 'c' } 

```

#### Filtering arrays

```js

const arr = ['a', 1, 'b', 2, 'c', 3];

filter(arr, (value, index) => index & 1); 

// => [ '1', '2', '3' ] 

```

#### Filtering typed arrays

```js

const typedArr = new Int32Array([1, 2, -3, -4, 5]);

filter(typedArr, i => i < 0);

// => Int32Array [ -3, -4 ]

```

#### Filtering plain objects

```js

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 } 

```