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<?php // given: $undef = "\0"; //unset($undef); $null = NULL; $false = FALSE; $true = TRUE; // these operations: var_dump(isset($undef)); var_dump(empty($undef)); var_dump(array_key_exists('undef', $GLOBALS)); // "defined" below
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/hJ0od
function name:  (null)
number of ops:  18
compiled vars:  !0 = $undef, !1 = $null, !2 = $false, !3 = $true
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%00'
    5     1        ASSIGN                                                   !1, null
    6     2        ASSIGN                                                   !2, <false>
    7     3        ASSIGN                                                   !3, <true>
   11     4        INIT_FCALL                                               'var_dump'
          5        ISSET_ISEMPTY_CV                                 ~8      !0
          6        SEND_VAL                                                 ~8
          7        DO_ICALL                                                 
   12     8        INIT_FCALL                                               'var_dump'
          9        ISSET_ISEMPTY_CV                                 ~10     !0
         10        SEND_VAL                                                 ~10
         11        DO_ICALL                                                 
   13    12        INIT_FCALL                                               'var_dump'
         13        FETCH_R                      global              ~12     'GLOBALS'
         14        ARRAY_KEY_EXISTS                                 ~13     'undef', ~12
         15        SEND_VAL                                                 ~13
         16        DO_ICALL                                                 
         17      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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