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<?php $test = array('t1'=> NULL); $a = null; var_dump(isset($a)); var_dump($test); var_dump($test['t1']); var_dump(isset($test['t1']));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/3TZv9
function name:  (null)
number of ops:  18
compiled vars:  !0 = $test, !1 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, <array>
    4     1        ASSIGN                                                   !1, null
    5     2        INIT_FCALL                                               'var_dump'
          3        ISSET_ISEMPTY_CV                                 ~4      !1
          4        SEND_VAL                                                 ~4
          5        DO_ICALL                                                 
    7     6        INIT_FCALL                                               'var_dump'
          7        SEND_VAR                                                 !0
          8        DO_ICALL                                                 
    8     9        INIT_FCALL                                               'var_dump'
         10        FETCH_DIM_R                                      ~7      !0, 't1'
         11        SEND_VAL                                                 ~7
         12        DO_ICALL                                                 
    9    13        INIT_FCALL                                               'var_dump'
         14        ISSET_ISEMPTY_DIM_OBJ                         0  ~9      !0, 't1'
         15        SEND_VAL                                                 ~9
         16        DO_ICALL                                                 
         17      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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