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<?php $txt = 'dog blah crocodile blah dog blah cat blah crocodile blah dog blah crocodile blah dog blah cat blah dog blah cat blah crocodile blah dog blah crocodile blah mice blah cat blah crocodile'; echo preg_replace('/(?:dog|mice)(?:(?!dog|mice|cat).)* \Kcrocodile(?= (?:(?!dog|mice|cat).)* (?:dog|mice))/', 'replacement', $txt);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/mYb90
function name:  (null)
number of ops:  8
compiled vars:  !0 = $txt
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 'dog+blah+crocodile+blah+dog+blah+cat+blah+crocodile+blah+dog+blah+crocodile+blah+dog+blah+cat+blah+dog+blah+cat+blah+crocodile+blah+dog+blah+crocodile+blah+mice+blah+cat+blah+crocodile'
    5     1        INIT_FCALL                                               'preg_replace'
          2        SEND_VAL                                                 '%2F%28%3F%3Adog%7Cmice%29%28%3F%3A%28%3F%21dog%7Cmice%7Ccat%29.%29%2A+%5CKcrocodile%28%3F%3D+%28%3F%3A%28%3F%21dog%7Cmice%7Ccat%29.%29%2A+%28%3F%3Adog%7Cmice%29%29%2F'
          3        SEND_VAL                                                 'replacement'
          4        SEND_VAR                                                 !0
          5        DO_ICALL                                         $2      
          6        ECHO                                                     $2
          7      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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