defined

return the first argument that is !== undefined

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

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var defined = require('defined');
var opts = { y : false, w : 4 };
var x = defined(opts.x, opts.y, opts.w, 100);
console.log(x);

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$ node example/defined.js
false

The return value is false because false is the first item that is !== undefined.

methods

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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 do:

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npm install defined

license

MIT