3v4l.org

run code in 300+ PHP versions simultaneously
<?php $header = array('test'); if (isset($header[0]['class'])) { echo $header[0]; } else { echo 'not set'; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 4, Position 2 = 7
Branch analysis from position: 4
1 jumps found. (Code = 42) Position 1 = 8
Branch analysis from position: 8
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 7
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/RYVL4
function name:  (null)
number of ops:  9
compiled vars:  !0 = $header
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, <array>
    3     1        FETCH_DIM_IS                                     ~2      !0, 0
          2        ISSET_ISEMPTY_DIM_OBJ                         0          ~2, 'class'
          3      > JMPZ                                                     ~3, ->7
    4     4    >   FETCH_DIM_R                                      ~4      !0, 0
          5        ECHO                                                     ~4
          6      > JMP                                                      ->8
    7     7    >   ECHO                                                     'not+set'
    8     8    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


preferences:
150.07 ms | 1393 KiB | 13 Q