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<?php // $_GET['myvar'] is unset echo $_GET['myvar'] ?? '' == 'hello' ? "true\n" : "false\n"; // $_GET['myvar'] is set but != 'hello' $_GET['myvar'] = 'farewell'; echo $_GET['myvar'] ?? '' == 'hello' ? "true\n" : "false\n"; // $_GET['myvar'] is set and == 'hello' $_GET['myvar'] = 'hello'; echo $_GET['myvar'] ?? '' == 'hello' ? "true\n" : "false\n"; // $_GET['myvar'] is set but "falsey" $_GET['myvar'] = 0; echo $_GET['myvar'] ?? '' == 'hello' ? "true\n" : "false\n"; $_GET['myvar'] = ''; echo $_GET['myvar'] ?? '' == 'hello' ? "true\n" : "false\n";
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 5, Position 2 = 7
Branch analysis from position: 5
1 jumps found. (Code = 42) Position 1 = 8
Branch analysis from position: 8
2 jumps found. (Code = 43) Position 1 = 17, Position 2 = 19
Branch analysis from position: 17
1 jumps found. (Code = 42) Position 1 = 20
Branch analysis from position: 20
2 jumps found. (Code = 43) Position 1 = 29, Position 2 = 31
Branch analysis from position: 29
1 jumps found. (Code = 42) Position 1 = 32
Branch analysis from position: 32
2 jumps found. (Code = 43) Position 1 = 41, Position 2 = 43
Branch analysis from position: 41
1 jumps found. (Code = 42) Position 1 = 44
Branch analysis from position: 44
2 jumps found. (Code = 43) Position 1 = 53, Position 2 = 55
Branch analysis from position: 53
1 jumps found. (Code = 42) Position 1 = 56
Branch analysis from position: 56
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 55
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 43
2 jumps found. (Code = 43) Position 1 = 53, Position 2 = 55
Branch analysis from position: 53
Branch analysis from position: 55
Branch analysis from position: 31
2 jumps found. (Code = 43) Position 1 = 41, Position 2 = 43
Branch analysis from position: 41
Branch analysis from position: 43
Branch analysis from position: 19
2 jumps found. (Code = 43) Position 1 = 29, Position 2 = 31
Branch analysis from position: 29
Branch analysis from position: 31
Branch analysis from position: 7
2 jumps found. (Code = 43) Position 1 = 17, Position 2 = 19
Branch analysis from position: 17
Branch analysis from position: 19
filename:       /in/73sJS
function name:  (null)
number of ops:  58
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    4     0  E >   FETCH_IS                                         ~0      '_GET'
          1        FETCH_DIM_IS                                     ~1      ~0, 'myvar'
          2        COALESCE                                         ~2      ~1
          3        QM_ASSIGN                                        ~2      <false>
          4      > JMPZ                                                     ~2, ->7
          5    >   QM_ASSIGN                                        ~3      'true%0A'
          6      > JMP                                                      ->8
          7    >   QM_ASSIGN                                        ~3      'false%0A'
          8    >   ECHO                                                     ~3
    7     9        FETCH_W                      global              $4      '_GET'
         10        ASSIGN_DIM                                               $4, 'myvar'
         11        OP_DATA                                                  'farewell'
    8    12        FETCH_IS                                         ~6      '_GET'
         13        FETCH_DIM_IS                                     ~7      ~6, 'myvar'
         14        COALESCE                                         ~8      ~7
         15        QM_ASSIGN                                        ~8      <false>
         16      > JMPZ                                                     ~8, ->19
         17    >   QM_ASSIGN                                        ~9      'true%0A'
         18      > JMP                                                      ->20
         19    >   QM_ASSIGN                                        ~9      'false%0A'
         20    >   ECHO                                                     ~9
   11    21        FETCH_W                      global              $10     '_GET'
         22        ASSIGN_DIM                                               $10, 'myvar'
         23        OP_DATA                                                  'hello'
   12    24        FETCH_IS                                         ~12     '_GET'
         25        FETCH_DIM_IS                                     ~13     ~12, 'myvar'
         26        COALESCE                                         ~14     ~13
         27        QM_ASSIGN                                        ~14     <false>
         28      > JMPZ                                                     ~14, ->31
         29    >   QM_ASSIGN                                        ~15     'true%0A'
         30      > JMP                                                      ->32
         31    >   QM_ASSIGN                                        ~15     'false%0A'
         32    >   ECHO                                                     ~15
   15    33        FETCH_W                      global              $16     '_GET'
         34        ASSIGN_DIM                                               $16, 'myvar'
         35        OP_DATA                                                  0
   16    36        FETCH_IS                                         ~18     '_GET'
         37        FETCH_DIM_IS                                     ~19     ~18, 'myvar'
         38        COALESCE                                         ~20     ~19
         39        QM_ASSIGN                                        ~20     <false>
         40      > JMPZ                                                     ~20, ->43
         41    >   QM_ASSIGN                                        ~21     'true%0A'
         42      > JMP                                                      ->44
         43    >   QM_ASSIGN                                        ~21     'false%0A'
         44    >   ECHO                                                     ~21
   17    45        FETCH_W                      global              $22     '_GET'
         46        ASSIGN_DIM                                               $22, 'myvar'
         47        OP_DATA                                                  ''
   18    48        FETCH_IS                                         ~24     '_GET'
         49        FETCH_DIM_IS                                     ~25     ~24, 'myvar'
         50        COALESCE                                         ~26     ~25
         51        QM_ASSIGN                                        ~26     <false>
         52      > JMPZ                                                     ~26, ->55
         53    >   QM_ASSIGN                                        ~27     'true%0A'
         54      > JMP                                                      ->56
         55    >   QM_ASSIGN                                        ~27     'false%0A'
         56    >   ECHO                                                     ~27
         57      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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