existential-assign

Check for the existential value of a variable/object. Assign one if the value doesn't exist.

Very useful to setup a object with default values if the user preferences are empty. Works fine with deep objects:

var defaults = {
  timeout: 3000,
  cb: function() {},
  user: {
    name: 'someone'
    url: 'github.com'
  }
}

var objt = {
  user: {
    name: 'Kiko Beats'
    url: 'github.com'
  }
}

existsAssign(defaults, objt)
// {
//   timeout: 3000,
//   cb: function() {},
//   user: {
//     name: 'Kiko Beats'
//     url: 'github.com'
//   }
// }

Notes that is slightly different than Object.assign.

Install

npm install existential-assign

If you want to use in the browser (powered by Browserify):

bower install existential-assign --save

and later link in your HTML:

<script src="bower_components/existential-assign/dist/existential-assign.js"></script>

Usage

First load the library:

var existsAssign = require('existential-assign');

Working with something that is not a Object:

existsAssign('hello world', null); // => 'hello world'
existsAssign('world', 'hello'); // => 'hello'

Working with Object:

existsAssign({hello: 'world'}, null) // => {hello: 'world'}
existsAssign({hello: 'Aloha'}, {hello: 'world'}) // => {hello: 'world'}

You can provide more than one source:

existsAssign({hello: 'world'}, null, undefined) // => {hello: 'world'}

It's equivalent to:

existsAssign(existsAssign({hello: 'world'}, null), undefined) // => {hello: 'world'}

License

MIT © Kiko Beats