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<?php if (empty($mystring)) { echo 'empty'; } if ($mystring == null) { echo 'null'; // and warning } if (!isset($mystring)) { echo 'not set'; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 2, Position 2 = 3
Branch analysis from position: 2
2 jumps found. (Code = 43) Position 1 = 5, Position 2 = 6
Branch analysis from position: 5
2 jumps found. (Code = 43) Position 1 = 9, Position 2 = 10
Branch analysis from position: 9
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 10
Branch analysis from position: 6
Branch analysis from position: 3
filename:       /in/URa8J
function name:  (null)
number of ops:  11
compiled vars:  !0 = $mystring
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ISSET_ISEMPTY_CV                                         !0
          1      > JMPZ                                                     ~1, ->3
    4     2    >   ECHO                                                     'empty'
    6     3    >   IS_EQUAL                                                 !0, null
          4      > JMPZ                                                     ~2, ->6
    7     5    >   ECHO                                                     'null'
    9     6    >   ISSET_ISEMPTY_CV                                 ~3      !0
          7        BOOL_NOT                                         ~4      ~3
          8      > JMPZ                                                     ~4, ->10
   10     9    >   ECHO                                                     'not+set'
   11    10    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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149.32 ms | 1397 KiB | 13 Q