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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 | |