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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/FpPfM
function name:  (null)
number of ops:  13
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ISSET_ISEMPTY_CV                                 ~1      !0
          1        CAST                                          4  ~2      ~1
          2        ECHO                                                     ~2
    3     3        ISSET_ISEMPTY_CV                                 ~3      !0
          4        CAST                                          4  ~4      ~3
          5        ECHO                                                     ~4
    4     6        TYPE_CHECK                                    2  ~5      !0
          7        CAST                                          4  ~6      ~5
          8        ECHO                                                     ~6
    5     9        CAST                                          4  ~7      null
         10        IS_IDENTICAL                                     ~8      !0, ~7
         11        ECHO                                                     ~8
         12      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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