jQuery.clean使用方法及思路分析

                     // 在ie9以下浏览器中,字符串以空白字符串开头,将空白字符串作为div元素的第一个文本子节点
                     if ( !jQuery.support.leadingWhitespace && rleadingWhitespace.test( elem ) ) {
                         div.insertBefore( context.createTextNode( rleadingWhitespace.exec(elem)[0] ), div.firstChild );
                     }
                     // 获取已经处理完毕的div子节点集合(nodeList对象)
                     elem = div.childNodes;
                     // Take out of fragment container (we need a fresh div each time)
                     // 在下一次循环处理字符串数组项前,清除处理创建过的div元素
                     div.parentNode.removeChild( div );
                 }
             }
             // 如果elem为DOM节点(文本节点)
             if ( elem.nodeType ) {
                 ret.push( elem );
             }
             // 将nodeList对象中节点合并到返回的数组中
             else {
                 jQuery.merge( ret, elem );
             }
         }
         // Fix #11356: Clear elements from safeFragment
         if ( div ) {
             elem = div = safe = null;
         }