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<?php $var = 0; // Evaluates to true because $var is empty if (empty($var)) { echo "$var is either 0, empty, or not set at all "; echo "<br />"; } // Evaluates as true because $var is set if (isset($var)) { echo "$var is set even though it is empty"; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 3, Position 2 = 7
Branch analysis from position: 3
2 jumps found. (Code = 43) Position 1 = 9, Position 2 = 12
Branch analysis from position: 9
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 12
Branch analysis from position: 7
filename:       /in/54PHQ
function name:  (null)
number of ops:  13
compiled vars:  !0 = $var
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 0
    6     1        ISSET_ISEMPTY_CV                                         !0
          2      > JMPZ                                                     ~2, ->7
    7     3    >   NOP                                                      
          4        FAST_CONCAT                                      ~3      !0, '+is+either+0%2C+empty%2C+or+not+set+at+all+'
          5        ECHO                                                     ~3
    8     6        ECHO                                                     '%3Cbr+%2F%3E'
   12     7    >   ISSET_ISEMPTY_CV                                         !0
          8      > JMPZ                                                     ~4, ->12
   13     9    >   NOP                                                      
         10        FAST_CONCAT                                      ~5      !0, '+is+set+even+though+it+is+empty'
         11        ECHO                                                     ~5
   14    12    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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