README.md

collection-map

Returns an array of mapped values from an array or object.

Install

Install with npm:

$ npm install --save collection-map

Inspired by the collections/map util in mout.

Usage

var map = require('collection-map');

objects

var res = map({a: 'foo', b: 'bar', c: 'baz'}, function(item, key, obj) {
  return item;
});
console.log(res);
// => ['foo', 'bar', 'baz']

var res = map({a: 'foo', b: 'bar', c: 'baz'}, function(item, key, obj) {
  return key;
});
console.log(res);
// => ['a', 'b', 'c']

arrays

var res = map(['foo', 'bar', 'baz'], function(item, index, array) {
  return item;
});
console.log(res);
// => ['foo', 'bar', 'baz']

var res = map(['foo', 'bar', 'baz'], function(item, index, array) {
  return index;
});
console.log(res);
// => [0, 1, 2]

strings

A string may be passed as the second argument, for getting properties:

var obj = {
  a: {aaa: 'one', bbb: 'four', ccc: 'seven'},
  b: {aaa: 'two', bbb: 'five', ccc: 'eight'},
  c: {aaa: 'three', bbb: 'six', ccc: 'nine'}
};

console.log(map(obj, 'aaa'));
// => ['one', 'two', 'three']

var array = [obj.a, obj.b, obj.c];
console.log(map(array, 'bbb'));
// => ['four', 'five', 'six']

thisArg

Invocation context may be passed as the last argument.

var array = ['a', 'b', 'c'];
var ctx = {a: 'aaa', b: 'bbb', c: 'ccc'};

var res = map(array, function(item, index, array) {
  return this[item];
}, ctx);

console.log(res);
// => ['aaa', 'bbb', 'ccc']

About

Related projects

• arr-flatten: Recursively flatten an array or arrays. This is the fastest implementation of array flatten. | homepage
• arr-map: Faster, node.js focused alternative to JavaScript's native array map. | homepage
• for-in: Iterate over the own and inherited enumerable properties of an object, and return an object… more | homepage
• for-own: Iterate over the own enumerable properties of an object, and return an object with properties… more | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Running tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2017, Jon Schlinkert. Released under the MIT License.

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This file was generated by verb-generate-readme, v0.4.3, on March 02, 2017.