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<?php var_dump(substr('abc', -5)); var_dump(substr('abc', -5, 30)); var_dump(substr('abc', 0)); var_dump(substr('abc', 0, 10)); var_dump(substr('abc', 0, 0)); var_dump(substr('abc', 0, -10));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/aKs2O
function name:  (null)
number of ops:  47
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                                                 'abc'
          3        SEND_VAL                                                 -5
          4        DO_ICALL                                         $0      
          5        SEND_VAR                                                 $0
          6        DO_ICALL                                                 
    4     7        INIT_FCALL                                               'var_dump'
          8        INIT_FCALL                                               'substr'
          9        SEND_VAL                                                 'abc'
         10        SEND_VAL                                                 -5
         11        SEND_VAL                                                 30
         12        DO_ICALL                                         $2      
         13        SEND_VAR                                                 $2
         14        DO_ICALL                                                 
    5    15        INIT_FCALL                                               'var_dump'
         16        INIT_FCALL                                               'substr'
         17        SEND_VAL                                                 'abc'
         18        SEND_VAL                                                 0
         19        DO_ICALL                                         $4      
         20        SEND_VAR                                                 $4
         21        DO_ICALL                                                 
    6    22        INIT_FCALL                                               'var_dump'
         23        INIT_FCALL                                               'substr'
         24        SEND_VAL                                                 'abc'
         25        SEND_VAL                                                 0
         26        SEND_VAL                                                 10
         27        DO_ICALL                                         $6      
         28        SEND_VAR                                                 $6
         29        DO_ICALL                                                 
    7    30        INIT_FCALL                                               'var_dump'
         31        INIT_FCALL                                               'substr'
         32        SEND_VAL                                                 'abc'
         33        SEND_VAL                                                 0
         34        SEND_VAL                                                 0
         35        DO_ICALL                                         $8      
         36        SEND_VAR                                                 $8
         37        DO_ICALL                                                 
    8    38        INIT_FCALL                                               'var_dump'
         39        INIT_FCALL                                               'substr'
         40        SEND_VAL                                                 'abc'
         41        SEND_VAL                                                 0
         42        SEND_VAL                                                 -10
         43        DO_ICALL                                         $10     
         44        SEND_VAR                                                 $10
         45        DO_ICALL                                                 
         46      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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