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<?php $a = array('l' => foo); var_dump(isset($a[null])); var_dump(isset($a['4'])); var_dump(isset($a['l']));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/r3fJ0
function name:  (null)
number of ops:  16
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   FETCH_CONSTANT                                   ~1      'foo'
          1        INIT_ARRAY                                       ~2      ~1, 'l'
          2        ASSIGN                                                   !0, ~2
    5     3        INIT_FCALL                                               'var_dump'
          4        ISSET_ISEMPTY_DIM_OBJ                         0  ~4      !0, null
          5        SEND_VAL                                                 ~4
          6        DO_ICALL                                                 
    6     7        INIT_FCALL                                               'var_dump'
          8        ISSET_ISEMPTY_DIM_OBJ                         0  ~6      !0, 4
          9        SEND_VAL                                                 ~6
         10        DO_ICALL                                                 
    7    11        INIT_FCALL                                               'var_dump'
         12        ISSET_ISEMPTY_DIM_OBJ                         0  ~8      !0, 'l'
         13        SEND_VAL                                                 ~8
         14        DO_ICALL                                                 
         15      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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