RE: window. or this. prefix

by mikewse :: Rate this Message:

I've wanted to find a better version of 'var dwr = {};' for a while, mostly because every JS checker complains. I'm not sure why.

I think they expect a statement and not a declaration in the one-liner. Same problem we had with Safari and "if ( expr ) function()...".

As we want "dwr" in the global scope it would do fine without a |var| declaration though.

It's worse that when used with an 'if' we might like to use a block, but { var dwr = {}; } feels like it shouldn't affect the surroundings. (though I appreciate that it does).

Well, |var|-declared variables in JavaScript register themselves in the nearest scope and new scopes are created for functions, not for individual {} blocks.

So doing window['dwr'] felt like a decent fix, however, and this is the strange bit, on IE:

window['dwr'] = { };
dwr.wibble = 'x';
if (dwr == null) var dwr = {};

Ends up re-defining dwr because (dwr == null) is true. I have no idea why, but IE was broken because not all declarations of DWR did it in the same way.

I've tried but can't trigger this bug. Anything else I need to do?

In the end I copied what Dojo does.

Ok, they have a lot of handling for other environments than the browser. In the browser this===window. For that reason I think the current |this| code would work just the same with |window|.

If the aim is to always register our variables on the global object I think it is clearer to use |window|.

Best regards

Mike

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