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<?php $header = array('test'); var_dump($header); var_dump($header[0]['class']); die(); if (isset($header[0]['class'])) { echo 'set'; } else { echo 'not set'; }
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 79) Position 1 = -2
filename:       /in/7aRTP
function name:  (null)
number of ops:  17
compiled vars:  !0 = $header
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, <array>
    4     1        INIT_FCALL                                               'var_dump'
          2        SEND_VAR                                                 !0
          3        DO_ICALL                                                 
    5     4        INIT_FCALL                                               'var_dump'
          5        FETCH_DIM_R                                      ~3      !0, 0
          6        FETCH_DIM_R                                      ~4      ~3, 'class'
          7        SEND_VAL                                                 ~4
          8        DO_ICALL                                                 
    6     9      > EXIT                                                     
    7    10*       FETCH_DIM_IS                                     ~6      !0, 0
         11*       ISSET_ISEMPTY_DIM_OBJ                         0          ~6, 'class'
         12*       JMPZ                                                     ~7, ->15
    8    13*       ECHO                                                     'set'
         14*       JMP                                                      ->16
   11    15*       ECHO                                                     'not+set'
   12    16*     > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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