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<?php $a = '0123456789'; echo 'mb_substr($a, 0, -1)', @mb_substr($a, 0, -1), "\n"; echo 'mb_substr($a, -1)', @mb_substr($a, -1), "\n";
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/DScVf
function name:  (null)
number of ops:  21
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, '0123456789'
    3     1        ECHO                                                     'mb_substr%28%24a%2C+0%2C+-1%29'
          2        BEGIN_SILENCE                                    ~2      
          3        INIT_FCALL                                               'mb_substr'
          4        SEND_VAR                                                 !0
          5        SEND_VAL                                                 0
          6        SEND_VAL                                                 -1
          7        DO_ICALL                                         $3      
          8        END_SILENCE                                              ~2
          9        ECHO                                                     $3
         10        ECHO                                                     '%0A'
    4    11        ECHO                                                     'mb_substr%28%24a%2C+-1%29'
         12        BEGIN_SILENCE                                    ~4      
         13        INIT_FCALL                                               'mb_substr'
         14        SEND_VAR                                                 !0
         15        SEND_VAL                                                 -1
         16        DO_ICALL                                         $5      
         17        END_SILENCE                                              ~4
         18        ECHO                                                     $5
         19        ECHO                                                     '%0A'
         20      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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