+ var fragment = document.createDocumentFragment();
+ fragment.appendChild( div.firstChild );
+
+ // WebKit doesn't clone checked state correctly in fragments
+ jQuery.support.checkClone = fragment.cloneNode(true).cloneNode(true).lastChild.checked;
+
+ // Figure out if the W3C box model works as expected
+ // document.body must exist before we can do this
+ jQuery(function() {
+ var div = document.createElement("div");
+ div.style.width = div.style.paddingLeft = "1px";
+
+ document.body.appendChild( div );
+ jQuery.boxModel = jQuery.support.boxModel = div.offsetWidth === 2;
+
+ // Check if natively block-level elements act like inline-block
+ // elements when setting their display to 'inline'
+ // (IE < 8 does this)
+ if ( 'zoom' in div.style ) {
+ div.style.display = 'inline';
+
+ // Layout is necessary to trigger this “feature”
+ div.style.zoom = 1;
+ jQuery.support.inlineBlockNeedsLayout = div.offsetWidth === 2;
+ }
+
+ // Check if table cells still have offsetWidth/Height when they are set
+ // to display:none and there are still other visible table cells in a
+ // table row; if so, offsetWidth/Height are not reliable for use when
+ // determining if an element has been hidden directly using
+ // display:none (it is still safe to use offsets if a parent element is
+ // hidden; don safety goggles and see bug #4512 for more information).
+ // (only IE 8 fails this test)
+ div.innerHTML = '<table><tr><td style="display:none"></td><td>t</td></tr></table>';
+ jQuery.support.reliableHiddenOffsets = div.getElementsByTagName('td')[0].offsetHeight === 0;
+ div.innerHTML = '';
+
+ document.body.removeChild( div ).style.display = 'none';
+ div = null;
+ });
+
+ // Technique from Juriy Zaytsev
+ // http://thinkweb2.com/projects/prototype/detecting-event-support-without-browser-sniffing/
+ var eventSupported = function( eventName ) {
+ var el = document.createElement("div");
+ eventName = "on" + eventName;
+
+ var isSupported = (eventName in el);
+ if ( !isSupported ) {
+ el.setAttribute(eventName, "return;");
+ isSupported = typeof el[eventName] === "function";
+ }
+ el = null;
+
+ return isSupported;
+ };
+
+ jQuery.support.submitBubbles = eventSupported("submit");
+ jQuery.support.changeBubbles = eventSupported("change");
+
+ // release memory in IE
+ root = script = div = all = a = null;
+})();