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<?php $obj = new stdClass(); $obj->bar = "xyz"; $data = array("foo" => "bar"); $key = "foo"; // the good: without and within a string echo $obj->{$data[$key]}; echo "{$obj->{$data[$key]}}"; // the bad: echo $obj->${data[$key]}; // syntax error // complex curly brace syntax: without and within a string echo $obj->{${'data'}[$key]}; echo "{$obj->{${'data'}[$key]}}";
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/upm4G
function name:  (null)
number of ops:  27
compiled vars:  !0 = $obj, !1 = $data, !2 = $key
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   NEW                                              $3      'stdClass'
          1        DO_FCALL                                      0          
          2        ASSIGN                                                   !0, $3
    4     3        ASSIGN_OBJ                                               !0, 'bar'
          4        OP_DATA                                                  'xyz'
    5     5        ASSIGN                                                   !1, <array>
    6     6        ASSIGN                                                   !2, 'foo'
    9     7        FETCH_DIM_R                                      ~9      !1, !2
          8        FETCH_OBJ_R                                      ~10     !0, ~9
          9        ECHO                                                     ~10
   10    10        FETCH_DIM_R                                      ~11     !1, !2
         11        FETCH_OBJ_R                                      ~12     !0, ~11
         12        CAST                                          6  ~13     ~12
         13        ECHO                                                     ~13
   13    14        FETCH_CONSTANT                                   ~14     'data'
         15        FETCH_DIM_R                                      ~15     ~14, !2
         16        FETCH_R                      local               ~16     ~15
         17        FETCH_OBJ_R                                      ~17     !0, ~16
         18        ECHO                                                     ~17
   17    19        FETCH_DIM_R                                      ~18     !1, !2
         20        FETCH_OBJ_R                                      ~19     !0, ~18
         21        ECHO                                                     ~19
   18    22        FETCH_DIM_R                                      ~20     !1, !2
         23        FETCH_OBJ_R                                      ~21     !0, ~20
         24        CAST                                          6  ~22     ~21
         25        ECHO                                                     ~22
         26      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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