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<?php $str = 'Lorem ipsum'; var_dump($str[0]); var_dump(substr($str, 0, 1));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/WdK6r
function name:  (null)
number of ops:  14
compiled vars:  !0 = $str
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 'Lorem+ipsum'
    5     1        INIT_FCALL                                               'var_dump'
          2        FETCH_DIM_R                                      ~2      !0, 0
          3        SEND_VAL                                                 ~2
          4        DO_ICALL                                                 
    6     5        INIT_FCALL                                               'var_dump'
          6        INIT_FCALL                                               'substr'
          7        SEND_VAR                                                 !0
          8        SEND_VAL                                                 0
          9        SEND_VAL                                                 1
         10        DO_ICALL                                         $4      
         11        SEND_VAR                                                 $4
         12        DO_ICALL                                                 
         13      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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