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<?php var_dump(substr('abcde', 2, -3)); var_dump(substr('abcde', 2, -4)); var_dump(substr('ab', 2)); var_dump(substr('ab', 3)); var_dump(substr('ab', 0, -2)); var_dump(substr('ab', 0, -3));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/l7dq5
function name:  (null)
number of ops:  47
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   INIT_FCALL                                               'var_dump'
          1        INIT_FCALL                                               'substr'
          2        SEND_VAL                                                 'abcde'
          3        SEND_VAL                                                 2
          4        SEND_VAL                                                 -3
          5        DO_ICALL                                         $0      
          6        SEND_VAR                                                 $0
          7        DO_ICALL                                                 
    3     8        INIT_FCALL                                               'var_dump'
          9        INIT_FCALL                                               'substr'
         10        SEND_VAL                                                 'abcde'
         11        SEND_VAL                                                 2
         12        SEND_VAL                                                 -4
         13        DO_ICALL                                         $2      
         14        SEND_VAR                                                 $2
         15        DO_ICALL                                                 
    5    16        INIT_FCALL                                               'var_dump'
         17        INIT_FCALL                                               'substr'
         18        SEND_VAL                                                 'ab'
         19        SEND_VAL                                                 2
         20        DO_ICALL                                         $4      
         21        SEND_VAR                                                 $4
         22        DO_ICALL                                                 
    6    23        INIT_FCALL                                               'var_dump'
         24        INIT_FCALL                                               'substr'
         25        SEND_VAL                                                 'ab'
         26        SEND_VAL                                                 3
         27        DO_ICALL                                         $6      
         28        SEND_VAR                                                 $6
         29        DO_ICALL                                                 
    8    30        INIT_FCALL                                               'var_dump'
         31        INIT_FCALL                                               'substr'
         32        SEND_VAL                                                 'ab'
         33        SEND_VAL                                                 0
         34        SEND_VAL                                                 -2
         35        DO_ICALL                                         $8      
         36        SEND_VAR                                                 $8
         37        DO_ICALL                                                 
    9    38        INIT_FCALL                                               'var_dump'
         39        INIT_FCALL                                               'substr'
         40        SEND_VAL                                                 'ab'
         41        SEND_VAL                                                 0
         42        SEND_VAL                                                 -3
         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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