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<?php $string = <<<XML <?xml version='1.0'?> <document> <title>Forty What?</title> <from>Joe</from> <to>Jane</to> <body> I know that's the answer -- but what's the question? </body> </document> XML; $xml = simplexml_load_string($string); var_dump( !isset($xml->undefined), is_null($xml->undefined), $xml->undefined == null, $xml->undefined === null );
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/u8VZH
function name:  (null)
number of ops:  20
compiled vars:  !0 = $string, !1 = $xml
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%3C%3Fxml+version%3D%271.0%27%3F%3E+%0A%3Cdocument%3E%0A+%3Ctitle%3EForty+What%3F%3C%2Ftitle%3E%0A+%3Cfrom%3EJoe%3C%2Ffrom%3E%0A+%3Cto%3EJane%3C%2Fto%3E%0A+%3Cbody%3E%0A++I+know+that%27s+the+answer+--+but+what%27s+the+question%3F%0A+%3C%2Fbody%3E%0A%3C%2Fdocument%3E'
   15     1        INIT_FCALL                                               'simplexml_load_string'
          2        SEND_VAR                                                 !0
          3        DO_ICALL                                         $3      
          4        ASSIGN                                                   !1, $3
   17     5        INIT_FCALL                                               'var_dump'
   18     6        ISSET_ISEMPTY_PROP_OBJ                           ~5      !1, 'undefined'
          7        BOOL_NOT                                         ~6      ~5
          8        SEND_VAL                                                 ~6
   19     9        FETCH_OBJ_R                                      ~7      !1, 'undefined'
         10        TYPE_CHECK                                    2  ~8      ~7
         11        SEND_VAL                                                 ~8
   20    12        FETCH_OBJ_R                                      ~9      !1, 'undefined'
         13        IS_EQUAL                                         ~10     ~9, null
         14        SEND_VAL                                                 ~10
   21    15        FETCH_OBJ_R                                      ~11     !1, 'undefined'
         16        TYPE_CHECK                                    2  ~12     ~11
         17        SEND_VAL                                                 ~12
         18        DO_ICALL                                                 
   22    19      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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