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<?php $test = ''; $test = null; var_dump(isset($test)); echo $test; $test2 = ''; unset($test2); var_dump(isset($test2)); echo $test2;
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/1B2DV
function name:  (null)
number of ops:  15
compiled vars:  !0 = $test, !1 = $test2
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, ''
    4     1        ASSIGN                                                   !0, null
    5     2        INIT_FCALL                                               'var_dump'
          3        ISSET_ISEMPTY_CV                                 ~4      !0
          4        SEND_VAL                                                 ~4
          5        DO_ICALL                                                 
    6     6        ECHO                                                     !0
    8     7        ASSIGN                                                   !1, ''
    9     8        UNSET_CV                                                 !1
   10     9        INIT_FCALL                                               'var_dump'
         10        ISSET_ISEMPTY_CV                                 ~7      !1
         11        SEND_VAL                                                 ~7
         12        DO_ICALL                                                 
   11    13        ECHO                                                     !1
         14      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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