How to declare global variables when using the strict mode pragma

Question

It's considered good practice to use a self-invoking function to wrap strict mode compliant code, often called the strict mode pragma:

(function(){   "use strict";   // Strict code here }()); 

My question is how to declare global variables in this case? Three alternatives that I know of today:

Alternative 1:

var GLOB = {};  (function(){   "use strict"; }()); 

Alternative 2:

(function(){   "use strict";   window.GLOB = {}; }()); 

Alternative 3:

(function(win){   "use strict";   win.GLOB = {}; }(window)); 

Any preferences and motivations? Other options?

Answer 1

IMO alternative 3 is best. But it assumes that window represents the global scope - which is true for the browser but not for other JS environments (command line, Node.js, etc.).

The following will work across the board:

(function(globals){   "use strict";   globals.GLOB = {}; }(this)); 

Answer 2

I know this is an old question but there's one not mentioned way of getting global context:

(function(globals){   "use strict";   globals.GLOB = {}; }( (1,eval)('this') )); 

(1,eval)('this')

will evaluate this from global context, so you can paste this wherever you like and you will always get global context