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<?php error_reporting(~E_NOTICE); 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/eHoS0
function name:  (null)
number of ops:  16
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   INIT_FCALL                                               'error_reporting'
          1        SEND_VAL                                                 -9
          2        DO_ICALL                                                 
    3     3        ISSET_ISEMPTY_CV                                 ~2      !0
          4        CAST                                          4  ~3      ~2
          5        ECHO                                                     ~3
    4     6        ISSET_ISEMPTY_CV                                 ~4      !0
          7        CAST                                          4  ~5      ~4
          8        ECHO                                                     ~5
    5     9        TYPE_CHECK                                    2  ~6      !0
         10        CAST                                          4  ~7      ~6
         11        ECHO                                                     ~7
    6    12        CAST                                          4  ~8      null
         13        IS_IDENTICAL                                     ~9      !0, ~8
         14        ECHO                                                     ~9
         15      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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