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<?php var_dump(substr('a', 1)); var_dump(substr('a', 1, null)); var_dump(substr('a', 1, 0)); var_dump(substr('a', 1, 1)); var_dump(substr('', 0)); var_dump(substr('', 0, null)); var_dump(substr('', 0, 0)); var_dump(substr('', 0, 1)); var_dump(substr('', 1)); var_dump(substr('', 1, null)); var_dump(substr('', 1, 0)); var_dump(substr('', 1, 1));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/a96t9
function name:  (null)
number of ops:  94
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                                                 'a'
          3        SEND_VAL                                                 1
          4        DO_ICALL                                         $0      
          5        SEND_VAR                                                 $0
          6        DO_ICALL                                                 
    3     7        INIT_FCALL                                               'var_dump'
          8        INIT_FCALL                                               'substr'
          9        SEND_VAL                                                 'a'
         10        SEND_VAL                                                 1
         11        SEND_VAL                                                 null
         12        DO_ICALL                                         $2      
         13        SEND_VAR                                                 $2
         14        DO_ICALL                                                 
    4    15        INIT_FCALL                                               'var_dump'
         16        INIT_FCALL                                               'substr'
         17        SEND_VAL                                                 'a'
         18        SEND_VAL                                                 1
         19        SEND_VAL                                                 0
         20        DO_ICALL                                         $4      
         21        SEND_VAR                                                 $4
         22        DO_ICALL                                                 
    5    23        INIT_FCALL                                               'var_dump'
         24        INIT_FCALL                                               'substr'
         25        SEND_VAL                                                 'a'
         26        SEND_VAL                                                 1
         27        SEND_VAL                                                 1
         28        DO_ICALL                                         $6      
         29        SEND_VAR                                                 $6
         30        DO_ICALL                                                 
    6    31        INIT_FCALL                                               'var_dump'
         32        INIT_FCALL                                               'substr'
         33        SEND_VAL                                                 ''
         34        SEND_VAL                                                 0
         35        DO_ICALL                                         $8      
         36        SEND_VAR                                                 $8
         37        DO_ICALL                                                 
    7    38        INIT_FCALL                                               'var_dump'
         39        INIT_FCALL                                               'substr'
         40        SEND_VAL                                                 ''
         41        SEND_VAL                                                 0
         42        SEND_VAL                                                 null
         43        DO_ICALL                                         $10     
         44        SEND_VAR                                                 $10
         45        DO_ICALL                                                 
    8    46        INIT_FCALL                                               'var_dump'
         47        INIT_FCALL                                               'substr'
         48        SEND_VAL                                                 ''
         49        SEND_VAL                                                 0
         50        SEND_VAL                                                 0
         51        DO_ICALL                                         $12     
         52        SEND_VAR                                                 $12
         53        DO_ICALL                                                 
    9    54        INIT_FCALL                                               'var_dump'
         55        INIT_FCALL                                               'substr'
         56        SEND_VAL                                                 ''
         57        SEND_VAL                                                 0
         58        SEND_VAL                                                 1
         59        DO_ICALL                                         $14     
         60        SEND_VAR                                                 $14
         61        DO_ICALL                                                 
   10    62        INIT_FCALL                                               'var_dump'
         63        INIT_FCALL                                               'substr'
         64        SEND_VAL                                                 ''
         65        SEND_VAL                                                 1
         66        DO_ICALL                                         $16     
         67        SEND_VAR                                                 $16
         68        DO_ICALL                                                 
   11    69        INIT_FCALL                                               'var_dump'
         70        INIT_FCALL                                               'substr'
         71        SEND_VAL                                                 ''
         72        SEND_VAL                                                 1
         73        SEND_VAL                                                 null
         74        DO_ICALL                                         $18     
         75        SEND_VAR                                                 $18
         76        DO_ICALL                                                 
   12    77        INIT_FCALL                                               'var_dump'
         78        INIT_FCALL                                               'substr'
         79        SEND_VAL                                                 ''
         80        SEND_VAL                                                 1
         81        SEND_VAL                                                 0
         82        DO_ICALL                                         $20     
         83        SEND_VAR                                                 $20
         84        DO_ICALL                                                 
   13    85        INIT_FCALL                                               'var_dump'
         86        INIT_FCALL                                               'substr'
         87        SEND_VAL                                                 ''
         88        SEND_VAL                                                 1
         89        SEND_VAL                                                 1
         90        DO_ICALL                                         $22     
         91        SEND_VAR                                                 $22
         92        DO_ICALL                                                 
         93      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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