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<?php // Example 1 $null = null; echo $null['undefined']; // Example 2 $reference =& $undefined; // Example 3 $cookie =& $undefined ?? 'cookie'; echo $cookie . "\n"; // Example 4 $array = ['value']; $value =& $array[0]; $anotherArray = $array; $anotherArray[0] = 'surprise!'; echo $value . "\n";
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/uZNlq
function name:  (null)
number of ops:  19
compiled vars:  !0 = $null, !1 = $reference, !2 = $undefined, !3 = $cookie, !4 = $array, !5 = $value, !6 = $anotherArray
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    4     0  E >   ASSIGN                                                   !0, null
    5     1        FETCH_DIM_R                                      ~8      !0, 'undefined'
          2        ECHO                                                     ~8
    8     3        ASSIGN_REF                                               !1, !2
   11     4        ASSIGN_REF                                       $10     !3, !2
          5        COALESCE                                         ~11     $10
          6        QM_ASSIGN                                        ~11     'cookie'
          7        FREE                                                     ~11
   13     8        CONCAT                                           ~12     !3, '%0A'
          9        ECHO                                                     ~12
   16    10        ASSIGN                                                   !4, <array>
   18    11        FETCH_DIM_W                                      $14     !4, 0
         12        ASSIGN_REF                                               !5, $14
   20    13        ASSIGN                                                   !6, !4
   22    14        ASSIGN_DIM                                               !6, 0
         15        OP_DATA                                                  'surprise%21'
   24    16        CONCAT                                           ~18     !5, '%0A'
         17        ECHO                                                     ~18
         18      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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