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<?php $input = '{ "0": "data" }'; $result = json_decode($input); var_dump($result->{"0"}); $result->{"0"} = 1; var_dump($result->{"0"}); var_dump($result); // NULL
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/sJo8p
function name:  (null)
number of ops:  19
compiled vars:  !0 = $input, !1 = $result
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%7B+%220%22%3A+%22data%22+%7D'
    6     1        INIT_FCALL                                               'json_decode'
          2        SEND_VAR                                                 !0
          3        DO_ICALL                                         $3      
          4        ASSIGN                                                   !1, $3
    8     5        INIT_FCALL                                               'var_dump'
          6        FETCH_OBJ_R                                      ~5      !1, '0'
          7        SEND_VAL                                                 ~5
          8        DO_ICALL                                                 
    9     9        ASSIGN_OBJ                                               !1, '0'
         10        OP_DATA                                                  1
   10    11        INIT_FCALL                                               'var_dump'
         12        FETCH_OBJ_R                                      ~8      !1, '0'
         13        SEND_VAL                                                 ~8
         14        DO_ICALL                                                 
   12    15        INIT_FCALL                                               'var_dump'
         16        SEND_VAR                                                 !1
         17        DO_ICALL                                                 
         18      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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