PHP5.3
①Added "?:" operator ( 添加了？：操作符)
指的是三元运算符可以简写：
$x = true;
$rs = $x?:false;//$x?$x:false;
②Added lambda functions and closures
(增加了匿名函数和闭包)
③Added support for namespaces
(增加了命名空间的支持)
PHP5.4
①Added short array syntax support (添加了短数组语法的支持。)
数组可以像js那样写了[1,2,3]
②Added array dereferencing support.(添加了数组的延迟支持)
数组立即调用
③Added class member access on instantiation support
(对象也可以立即调用 e.g. （new foo）->bar() )
④<?= is now always available regardless of the short_open_tag_setting
(短标签的支持<h1><?=$title?></h1>)
⑤Added binary numbers format (0b001010)
增加二进制表示
⑥Added support for Traits
PHP5.5...未完待续...