Question

If passing params or an object full of properties into function, it’s useful to check for undefined params and give default values to those that are undefined.

Without using a library function like jQuery extent, what would be the shortest about of code to do this kind of assigning defaults?

Here is the shortest I can think of:

var test;
var output = (typeof test != "undefined") ? test : "Default";

Before someone suggests:

var test;
var output = test || "Default";

That will not work with false, 0 or “”

Answer 1

Try this:

var output = test != null ? test : "Default";

I.g:

null == undefined // true
null == null // true
null == 0 // false
null == "" //false
null == false // false