Function assert

documentation/javascript/application.js:4683–4694

( fn )

	// Used for testing something on an element
	assert = function( fn ) {
		var div = document.createElement("div");

		try {
			return fn( div );
		} catch (e) {
			return false;
		} finally {
			// release memory in IE
			div = null;
		}
	},

	// Check if getElementsByTagName("*") returns only elements
	assertTagNameNoComments = assert(function( div ) {