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<?php var_dump(substr('a', 0, 2)); // string(1) "a" var_dump(substr('', 0, 2)); // bool(false) var_dump(substr('a', 1)); // bool(false)
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/lNZ3N
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        FRAMELESS_ICALL_3                substr              ~0      'a', 0
          2        OP_DATA                                                      2
          3        SEND_VAL                                                     ~0
          4        DO_ICALL                                                     
    4     5        INIT_FCALL                                                   'var_dump'
          6        FRAMELESS_ICALL_3                substr              ~2      '', 0
          7        OP_DATA                                                      2
          8        SEND_VAL                                                     ~2
          9        DO_ICALL                                                     
    5    10        INIT_FCALL                                                   'var_dump'
         11        FRAMELESS_ICALL_2                substr              ~4      'a', 1
         12        SEND_VAL                                                     ~4
         13        DO_ICALL                                                     
         14      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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