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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:  24
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                                                 'a'
          3        SEND_VAL                                                 0
          4        SEND_VAL                                                 2
          5        DO_ICALL                                         $0      
          6        SEND_VAR                                                 $0
          7        DO_ICALL                                                 
    4     8        INIT_FCALL                                               'var_dump'
          9        INIT_FCALL                                               'substr'
         10        SEND_VAL                                                 ''
         11        SEND_VAL                                                 0
         12        SEND_VAL                                                 2
         13        DO_ICALL                                         $2      
         14        SEND_VAR                                                 $2
         15        DO_ICALL                                                 
    5    16        INIT_FCALL                                               'var_dump'
         17        INIT_FCALL                                               'substr'
         18        SEND_VAL                                                 'a'
         19        SEND_VAL                                                 1
         20        DO_ICALL                                         $4      
         21        SEND_VAR                                                 $4
         22        DO_ICALL                                                 
         23      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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