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@tsaniel
Forked from 140bytes/LICENSE.txt
Created October 5, 2011 10:05
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isWindow
function(
a, // input
b // placeholder for property document of a
){
return
// cannot be falsy value, mainly to prevent null and undefined (regarded as global object in some browsers)
!!a &&
// checking types with Object.prototype.toString.call is always a good way
// however, for window, is a bit difficult
// let's see the results in different browsers (except IE678, which return "[object Object]")
// "[object Window]"
// "[object DOMWindow]"
// "[object global]"
// so, we can simply check if the input's [[Class]] is ended with w] or l]
/[wl]]/.test({}.toString.call(a)) ||
// believe me, IE is not a good guy
// why?
// because in which, window == document but document != window
// what a wtf feature!
a == (b=a.document) && b != a
}
(function(a,b){return!!a&&/[wl]]/.test({}.toString.call(a))||a==(b=a.document)&&b!=a})
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
{
"name": "isWindow",
"description": "Check if the input is window.",
"keywords": [
"window",
"isWindow",
"DOM",
"jQUery"
]
}
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>true</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
// write a small example that shows off the API for your example
// and tests it in one fell swoop.
var myFunction = (function(a,b){return!!a&&/[wl]]/.test({}.toString.call(a))||a==(b=a.document)&&b!=a})
document.getElementById( "ret" ).innerHTML = myFunction(window)
</script>
@nikola
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nikola commented Dec 2, 2011

Clever. Exploiting the fact that any global object is exposed as a property of window, and window itself is a global object.

@tsaniel
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Author

tsaniel commented Dec 3, 2011

@phoetry: It's clever but it won't work.

var a = {};
a.window = a;
(function(a,b){return a&&a==a[b='window']&&a==a[b][b]})(a) // true

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