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# defined | |
return the first argument that is `!== undefined` | |
[](http://ci.testling.com/substack/defined) | |
[](http://travis-ci.org/substack/defined) | |
Most of the time when I chain together `||`s, I actually just want the first | |
item that is not `undefined`, not the first non-falsy item. | |
This module is like the defined-or (`//`) operator in perl 5.10+. | |
# example | |
``` js | |
var defined = require('defined'); | |
var opts = { y : false, w : 4 }; | |
var x = defined(opts.x, opts.y, opts.w, 100); | |
console.log(x); | |
``` | |
``` | |
$ node example/defined.js | |
false | |
``` | |
The return value is `false` because `false` is the first item that is | |
`!== undefined`. | |
# methods | |
``` js | |
var defined = require('defined') | |
``` | |
## var x = defined(a, b, c...) | |
Return the first item in the argument list `a, b, c...` that is `!== undefined`. | |
If all the items are `=== undefined`, return undefined. | |
# install | |
With [npm](https://npmjs.org) do: | |
``` | |
npm install defined | |
``` | |
# license | |
MIT | |