array.filter

Curried function deriving a new array containing items from given array for which predicate returns true. Supports unary function, RegExp, dot/bracket-notation string path, and compound query object as predicate.

npm install array.filter --save

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Overview

Similar to [].filter but more functional and compositionally friendly.

Features

• Supports all dot/bracket-notation string paths supported by selectn.
• Partial application is directly supported via currying (no need for Function.prototype.bind).
• ES3, ES5, CommonJS, AMD, and legacy-global compatible.
• Haskell style Parameter Order (allows for pointfree programming style).

API Example

Unary function predicate

var filter = require('array.filter')
var numbers = [1, 2, 3, 4, 5]
var even = function (x) { return x % 2 === 0 }

filter(even, numbers)
//=> [ 2, 4 ]

RegExp predicate

var filter = require('array.filter')
var hexval = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'A', 'B', 'C', 'D', 'E', 'F']
var number = /^\d$/

filter(number, hexval)
//=> [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9  ]

Dot-notation path string predicate

var filter = require('array.filter')
var messages = [
  { read: true },
  { read: true },
  { read: false }
]

filter('read', messages).length
//=> 2

Compound query predicate

var filter = require('array.filter')
var messages = [
  { type: 'sent', meta: { read: true } },
  { type: 'received', meta: { read: true } },
  { type: 'sent', meta: { read: false } }
]

filter({ type: 'sent', 'meta.read': false }, messages).length
//=> 1

API

filter(predicate, list)

arguments

• predicate (Function|RegExp|String|Object) Unary function, RegExp, dot/bracket-notation string path, or compound query object.
• list (array) Array to evaluate.

returns

• (array) New array containing items from given array for which predicate returns true.

Alternatives

• _.filter
• array-filter
• arr-filter
• arrayfilter
• curried-filter
• filter-array

Contributing

SEE: contributing.md

Licenses