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<?php var_dump(iconv_substr('',0,10,'utf-8')); var_dump(substr('',0,10)); var_dump(mb_substr('',0,10));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/Q52RB
function name:  (null)
number of ops:  23
compiled vars:  none
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   INIT_FCALL                                                   'var_dump'
          1        INIT_FCALL_BY_NAME                                           'iconv_substr'
          2        SEND_VAL_EX                                                  ''
          3        SEND_VAL_EX                                                  0
          4        SEND_VAL_EX                                                  10
          5        SEND_VAL_EX                                                  'utf-8'
          6        DO_FCALL                                          0  $0      
          7        SEND_VAR                                                     $0
          8        DO_ICALL                                                     
    4     9        INIT_FCALL                                                   'var_dump'
         10        FRAMELESS_ICALL_3                substr              ~2      '', 0
         11        OP_DATA                                                      10
         12        SEND_VAL                                                     ~2
         13        DO_ICALL                                                     
    5    14        INIT_FCALL                                                   'var_dump'
         15        INIT_FCALL                                                   'mb_substr'
         16        SEND_VAL                                                     ''
         17        SEND_VAL                                                     0
         18        SEND_VAL                                                     10
         19        DO_ICALL                                             $4      
         20        SEND_VAR                                                     $4
         21        DO_ICALL                                                     
         22      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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