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<?php echo (int) @isset( $a ); // false and w/o error msg echo (int) @empty( $a ); // true (false and 0 empty, too echo (int) @is_null( $a ); // true and error msg echo (int) @null === $a; // true and error msg
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/L7gIF
function name:  (null)
number of ops:  21
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   BEGIN_SILENCE                                    ~1      
          1        ISSET_ISEMPTY_CV                                 ~2      !0
          2        END_SILENCE                                              ~1
          3        CAST                                          4  ~3      ~2
          4        ECHO                                                     ~3
    3     5        BEGIN_SILENCE                                    ~4      
          6        ISSET_ISEMPTY_CV                                 ~5      !0
          7        END_SILENCE                                              ~4
          8        CAST                                          4  ~6      ~5
          9        ECHO                                                     ~6
    4    10        BEGIN_SILENCE                                    ~7      
         11        TYPE_CHECK                                    2  ~8      !0
         12        END_SILENCE                                              ~7
         13        CAST                                          4  ~9      ~8
         14        ECHO                                                     ~9
    5    15        BEGIN_SILENCE                                    ~10     
         16        END_SILENCE                                              ~10
         17        CAST                                          4  ~11     null
         18        IS_IDENTICAL                                     ~12     !0, ~11
         19        ECHO                                                     ~12
         20      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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