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<?php function myCheck($in) { return @isset($in); } $var1='Something'; $var2='var1'; echo 'Set:' . isset($$var2); $var2='nope'; echo 'Set:' . isset($$var2); $var2='var1'; echo 'Set:' . myCheck($$var2); $var2='nope'; echo 'Set:' . myCheck($$var2); ?>
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/MVXAd
function name:  (null)
number of ops:  24
compiled vars:  !0 = $var1, !1 = $var2
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    5     0  E >   ASSIGN                                                   !0, 'Something'
    7     1        ASSIGN                                                   !1, 'var1'
    8     2        ISSET_ISEMPTY_VAR                             4  ~4      !1
          3        CONCAT                                           ~5      'Set%3A', ~4
          4        ECHO                                                     ~5
    9     5        ASSIGN                                                   !1, 'nope'
   10     6        ISSET_ISEMPTY_VAR                             4  ~7      !1
          7        CONCAT                                           ~8      'Set%3A', ~7
          8        ECHO                                                     ~8
   13     9        ASSIGN                                                   !1, 'var1'
   14    10        INIT_FCALL                                               'mycheck'
         11        FETCH_R                      local               ~10     !1
         12        SEND_VAL                                                 ~10
         13        DO_FCALL                                      0  $11     
         14        CONCAT                                           ~12     'Set%3A', $11
         15        ECHO                                                     ~12
   15    16        ASSIGN                                                   !1, 'nope'
   16    17        INIT_FCALL                                               'mycheck'
         18        FETCH_R                      local               ~14     !1
         19        SEND_VAL                                                 ~14
         20        DO_FCALL                                      0  $15     
         21        CONCAT                                           ~16     'Set%3A', $15
         22        ECHO                                                     ~16
   19    23      > RETURN                                                   1

Function mycheck:
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/MVXAd
function name:  myCheck
number of ops:  6
compiled vars:  !0 = $in
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   RECV                                             !0      
    3     1        BEGIN_SILENCE                                    ~1      
          2        ISSET_ISEMPTY_CV                                 ~2      !0
          3        END_SILENCE                                              ~1
          4      > RETURN                                                   ~2
          5*     > RETURN                                                   null

End of function mycheck

Generated using Vulcan Logic Dumper, using php 8.0.0


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