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<?php $nullvar = array( 0 => array('a' => array('r' => NULL)), 1 => array('a' => array('r' => null)), ); if (isset($nullvar[0]['a']['r'])) { echo "set"; } else { echo "not set"; } if (is_null($nullvar[0]['a']['r'])) { echo "\nnull"; } else { echo "\nnot null"; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 5, Position 2 = 7
Branch analysis from position: 5
1 jumps found. (Code = 42) Position 1 = 8
Branch analysis from position: 8
2 jumps found. (Code = 43) Position 1 = 13, Position 2 = 15
Branch analysis from position: 13
1 jumps found. (Code = 42) Position 1 = 16
Branch analysis from position: 16
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 15
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 7
2 jumps found. (Code = 43) Position 1 = 13, Position 2 = 15
Branch analysis from position: 13
Branch analysis from position: 15
filename:       /in/56lv4
function name:  (null)
number of ops:  17
compiled vars:  !0 = $nullvar
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, <array>
    9     1        FETCH_DIM_IS                                     ~2      !0, 0
          2        FETCH_DIM_IS                                     ~3      ~2, 'a'
          3        ISSET_ISEMPTY_DIM_OBJ                         0          ~3, 'r'
          4      > JMPZ                                                     ~4, ->7
   10     5    >   ECHO                                                     'set'
          6      > JMP                                                      ->8
   12     7    >   ECHO                                                     'not+set'
   15     8    >   FETCH_DIM_R                                      ~5      !0, 0
          9        FETCH_DIM_R                                      ~6      ~5, 'a'
         10        FETCH_DIM_R                                      ~7      ~6, 'r'
         11        TYPE_CHECK                                    2          ~7
         12      > JMPZ                                                     ~8, ->15
   16    13    >   ECHO                                                     '%0Anull'
         14      > JMP                                                      ->16
   18    15    >   ECHO                                                     '%0Anot+null'
   19    16    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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