PHP5.5 perforance Inmprovement: nested calls call stack pre-allocated by compiler bundled opcode cache Generators: <?php function xrange($start,$end) {     for ($i=$start;$i <= $send;$i++) {         yield $i;     } foreach (xrange(0,5) as $i) {      echo $i,"\n"; } finally: <?php $db=mysqli_connect(); try{ call_some_function($db); }finally{ mysqli_close($db); } list() in foreach $names =[["john","smith"],["fred","johnson"]]; foreach($names as list($first,$last)){ echo $first,$last; } Const array/string Dereferncing: echo array(1,2,3)[0];//output 1 echo "foobar"[3];//output b echo[1,3,4][2];//output 4 empty() support for functions/expressions curl upload functionality rewritten simplified password hashing API