Function markFunction

2.1.1/test/jquery-2.1.1.js:869–872

* Mark a function for special use by Sizzle * @param {Function} fn The function to mark

( fn )

 * @param {Function} fn The function to mark
 */
function markFunction( fn ) {
	fn[ expando ] = true;
	return fn;
}

/**
 * Support testing using an element