What do parameters in a () at the tail-end of a function mean? (Javascript)

Question

In the following code, what does the last line do (the bit within the parenthesis)?

Is it related to Javascript closures?
Is it returning a variable?
Is there a way to write this code without using this short-hand?

Thanks!!

(function (window, $, my, undefined) {
    'use strict';

    if (!$) { throw 'jQuery not found.'; }

    my.someNamespace = {

        bla:null,
        blabla:null,

        init: function(){},
        bind: function(){}

    };
} (window, $, window.my = window.my || {}));

score 5 · Accepted Answer · answered Dec 16 '15 at 19:46

5

var x = 5;
(function(y){
   console.log(y); // will print 5
})(x);

It’s an Immediately-Invoked Function Expression, or IIFE for short. It executes immediately after it’s created. x is the passed parameter.

answered Dec 16 '15 at 19:46

void

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1

Surely you knew this is a duplicate? – Amit Dec 16 '15 at 19:48
1

@Amit probably not, OP was confused with the arguments of IIFE, and not what it is. – void Dec 16 '15 at 19:49
I wasn't even sure what it was called or what to search for (and believe me, I did do a search), so thanks for the quick response! – Sterling Bourne Dec 16 '15 at 19:49

What do parameters in a () at the tail-end of a function mean? (Javascript)

1 Answers1