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<?php $nullvar[0]= null; if (isset($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 = 6, Position 2 = 8
Branch analysis from position: 6
1 jumps found. (Code = 42) Position 1 = 9
Branch analysis from position: 9
2 jumps found. (Code = 43) Position 1 = 14, Position 2 = 16
Branch analysis from position: 14
1 jumps found. (Code = 42) Position 1 = 17
Branch analysis from position: 17
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 16
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 8
2 jumps found. (Code = 43) Position 1 = 14, Position 2 = 16
Branch analysis from position: 14
Branch analysis from position: 16
filename:       /in/W5VWG
function name:  (null)
number of ops:  18
compiled vars:  !0 = $nullvar
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN_DIM                                               !0, 0
          1        OP_DATA                                                  null
    6     2        FETCH_DIM_IS                                     ~2      !0, 0
          3        FETCH_DIM_IS                                     ~3      ~2, 'a'
          4        ISSET_ISEMPTY_DIM_OBJ                         0          ~3, 'r'
          5      > JMPZ                                                     ~4, ->8
    7     6    >   ECHO                                                     'set'
          7      > JMP                                                      ->9
    9     8    >   ECHO                                                     'not+set'
   12     9    >   FETCH_DIM_R                                      ~5      !0, 0
         10        FETCH_DIM_R                                      ~6      ~5, 'a'
         11        FETCH_DIM_R                                      ~7      ~6, 'r'
         12        TYPE_CHECK                                    2          ~7
         13      > JMPZ                                                     ~8, ->16
   13    14    >   ECHO                                                     '%0Anull'
         15      > JMP                                                      ->17
   15    16    >   ECHO                                                     '%0Anot+null'
   16    17    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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156.2 ms | 1394 KiB | 13 Q