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<?php $re = '/(?<=\[prev)( title="[^"]+")( cont="[^"]+" res="[^"]+")/m'; $str = '[prev title="sample1" cont="sample1a" res="sample1b" mw="1"][prev title="sample2" cont="sample2a" res="sample2b" mw="2"][prev title="sample3" cont="sample3a" res="sample3b" mw="3"].'; $result = preg_replace($re, '$2$1', $str); echo $result;
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/FuPpk
function name:  (null)
number of ops:  10
compiled vars:  !0 = $re, !1 = $str, !2 = $result
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%2F%28%3F%3C%3D%5C%5Bprev%29%28+title%3D%22%5B%5E%22%5D%2B%22%29%28+cont%3D%22%5B%5E%22%5D%2B%22+res%3D%22%5B%5E%22%5D%2B%22%29%2Fm'
    4     1        ASSIGN                                                   !1, '%5Bprev+title%3D%22sample1%22+cont%3D%22sample1a%22+res%3D%22sample1b%22+mw%3D%221%22%5D%5Bprev+title%3D%22sample2%22+cont%3D%22sample2a%22+res%3D%22sample2b%22+mw%3D%222%22%5D%5Bprev+title%3D%22sample3%22+cont%3D%22sample3a%22+res%3D%22sample3b%22+mw%3D%223%22%5D.'
    5     2        INIT_FCALL                                               'preg_replace'
          3        SEND_VAR                                                 !0
          4        SEND_VAL                                                 '%242%241'
          5        SEND_VAR                                                 !1
          6        DO_ICALL                                         $5      
          7        ASSIGN                                                   !2, $5
    6     8        ECHO                                                     !2
    7     9      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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