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<?php var_dump(substr('f', 257, 1), substr('f', -257, 1));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/JcYmO
function name:  (null)
number of ops:  15
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   INIT_FCALL                                               'var_dump'
          1        INIT_FCALL                                               'substr'
          2        SEND_VAL                                                 'f'
          3        SEND_VAL                                                 257
          4        SEND_VAL                                                 1
          5        DO_ICALL                                         $0      
          6        SEND_VAR                                                 $0
          7        INIT_FCALL                                               'substr'
          8        SEND_VAL                                                 'f'
          9        SEND_VAL                                                 -257
         10        SEND_VAL                                                 1
         11        DO_ICALL                                         $1      
         12        SEND_VAR                                                 $1
         13        DO_ICALL                                                 
         14      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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