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<?php $x = ''; $$x = 'empty'; var_dump( ${''} ); $x = 'red'; $$x = 'empty'; var_dump( ${'red'} );
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/sDeh7
function name:  (null)
number of ops:  13
compiled vars:  !0 = $x, !1 = $, !2 = $red
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, ''
    3     1        FETCH_W                      local               $4      !0
          2        ASSIGN                                                   $4, 'empty'
    4     3        INIT_FCALL                                               'var_dump'
          4        SEND_VAR                                                 !1
          5        DO_ICALL                                                 
    6     6        ASSIGN                                                   !0, 'red'
    7     7        FETCH_W                      local               $8      !0
          8        ASSIGN                                                   $8, 'empty'
    8     9        INIT_FCALL                                               'var_dump'
         10        SEND_VAR                                                 !2
         11        DO_ICALL                                                 
         12      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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