jQuery equivalent to Prototype array.last()

Question

Why not just use simple javascript?

var array=[1,2,3,4];
var lastEl = array[array.length-1];

You can write it as a method too, if you like (assuming prototype has not been included on your page):

Array.prototype.last = function() {return this[this.length-1];}

with slice():

var a = [1,2,3,4];
var lastEl = a.slice(-1)[0]; // 4
// a is still [1,2,3,4]

with pop();

var a = [1,2,3,4];
var lastEl = a.pop(); // 4
// a is now [1,2,3]

see https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array for more information

When dealing with a jQuery object, .last() will do just that, filter the matched elements to only the last one in the set.

Of course, you can wrap a native array with jQuery leading to this:

var a = [1,2,3,4];
var lastEl = $(a).last()[0];

Why not use the get function?

var a = [1,2,3,4];
var last = $(a).get(-1);

http://api.jquery.com/get/ More info

Edit: As pointed out by DelightedD0D, this isn't the correct function to use as per jQuery's docs but it does still provide the correct results. I recommend using Salty's answer to keep your code correct.

For arrays, you could simply retrieve the last element position with array.length - 1:

var a = [1,2,3,4];

var lastEl = a[a.length-1]; // 4

In jQuery you have the :last selector, but this won't help you on plain arrays.