function assert(fn) {
	        var el = document.createElement("fieldset");

	        try {
	            return !!fn(el);
	        } catch (e) {
	            return false;
	        } finally {
	            // Remove from its parent by default
	            if (el.parentNode) {
	                el.parentNode.removeChild(el);
	            }
	            // release memory in IE
	            el = null;
	        }
	    }
/**
	     * Support testing using an element
	     * @param {Function} fn Passed the created element and returns a boolean result
	     */
Support testing using an element
@param {Function} fn Passed the created element and returns a boolean result
Support testing using an element @param { Function } fn Passed the created element and returns a boolean result
function assert(fn) {
	        var el = document.createElement("fieldset");
	        try {
	            return !!fn(el);
	        } catch (e) {
	            return false;
	        } finally {
	            if (el.parentNode) {
	                el.parentNode.removeChild(el);
	            }
	            el = null;
	        }
	    }
function assert ( fn ) { var el = document . createElement ( "fieldset" ) ; try { return ! ! fn ( el ) ; } catch ( e ) { return false ; } finally { if ( el . parentNode ) { el . parentNode . removeChild ( el ) ; } el = null ; } }
Support testing using an element
 @param {Function} fn Passed the created element and returns a boolean result
Support testing using an element @param { Function } fn Passed the created element and returns a boolean result
// Remove from its parent by default // release memory in IE