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<?php echo strtolower(preg_replace("/(?!^)(?=[A-Z])/", "_", "FooBar"));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/YtEiS
function name:  (null)
number of ops:  10
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   INIT_FCALL                                               'strtolower'
          1        INIT_FCALL                                               'preg_replace'
          2        SEND_VAL                                                 '%2F%28%3F%21%5E%29%28%3F%3D%5BA-Z%5D%29%2F'
          3        SEND_VAL                                                 '_'
          4        SEND_VAL                                                 'FooBar'
          5        DO_ICALL                                         $0      
          6        SEND_VAR                                                 $0
          7        DO_ICALL                                         $1      
          8        ECHO                                                     $1
          9      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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