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<?php $a['a']['b']['c'] = ($a['a']['b']['c'] ?? 0) + 1; echo json_encode($a), PHP_EOL; $a['a']['b']['c'] = ($a['a']['b']['c'] ?? 0) + 1; echo json_encode($a), PHP_EOL;
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/sdX97
function name:  (null)
number of ops:  31
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   FETCH_DIM_IS                                     ~4      !0, 'a'
          1        FETCH_DIM_IS                                     ~5      ~4, 'b'
          2        FETCH_DIM_IS                                     ~6      ~5, 'c'
          3        COALESCE                                         ~7      ~6
          4        QM_ASSIGN                                        ~7      0
          5        ADD                                              ~8      ~7, 1
          6        FETCH_DIM_W                                      $1      !0, 'a'
          7        FETCH_DIM_W                                      $2      $1, 'b'
          8        ASSIGN_DIM                                               $2, 'c'
          9        OP_DATA                                                  ~8
    4    10        INIT_FCALL                                               'json_encode'
         11        SEND_VAR                                                 !0
         12        DO_ICALL                                         $9      
         13        ECHO                                                     $9
         14        ECHO                                                     '%0A'
    6    15        FETCH_DIM_IS                                     ~13     !0, 'a'
         16        FETCH_DIM_IS                                     ~14     ~13, 'b'
         17        FETCH_DIM_IS                                     ~15     ~14, 'c'
         18        COALESCE                                         ~16     ~15
         19        QM_ASSIGN                                        ~16     0
         20        ADD                                              ~17     ~16, 1
         21        FETCH_DIM_W                                      $10     !0, 'a'
         22        FETCH_DIM_W                                      $11     $10, 'b'
         23        ASSIGN_DIM                                               $11, 'c'
         24        OP_DATA                                                  ~17
    7    25        INIT_FCALL                                               'json_encode'
         26        SEND_VAR                                                 !0
         27        DO_ICALL                                         $18     
         28        ECHO                                                     $18
         29        ECHO                                                     '%0A'
    8    30      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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