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<?php $a = false; echo "false is ".isset($a); $b = null; echo "null is ".isset($b);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/C9nSC
function name:  (null)
number of ops:  9
compiled vars:  !0 = $a, !1 = $b
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, <false>
    4     1        ISSET_ISEMPTY_CV                                 ~3      !0
          2        CONCAT                                           ~4      'false+is+', ~3
          3        ECHO                                                     ~4
    6     4        ASSIGN                                                   !1, null
    7     5        ISSET_ISEMPTY_CV                                 ~6      !1
          6        CONCAT                                           ~7      'null+is+', ~6
          7        ECHO                                                     ~7
          8      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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