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<?php echo preg_replace( '/(^|[a-z])([A-Z])/e', 'strtolower(strlen("\\1") ? "\\1_\\2" : "\\2")', $word );
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/Q5U5J
function name:  (null)
number of ops:  7
compiled vars:  !0 = $word
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   INIT_FCALL                                               'preg_replace'
    3     1        SEND_VAL                                                 '%2F%28%5E%7C%5Ba-z%5D%29%28%5BA-Z%5D%29%2Fe'
    4     2        SEND_VAL                                                 'strtolower%28strlen%28%22%5C1%22%29+%3F+%22%5C1_%5C2%22+%3A+%22%5C2%22%29'
    5     3        SEND_VAR                                                 !0
          4        DO_ICALL                                         $1      
          5        ECHO                                                     $1
    6     6      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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