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<?php $formval = "0"; if (isset($formval)) { echo "is set\n"; } $defined = null; var_dump(is_null($defined)); var_dump(is_null($undefined));
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 3, Position 2 = 4
Branch analysis from position: 3
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 4
filename:       /in/8N1Be
function name:  (null)
number of ops:  14
compiled vars:  !0 = $formval, !1 = $defined, !2 = $undefined
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, '0'
    4     1        ISSET_ISEMPTY_CV                                         !0
          2      > JMPZ                                                     ~4, ->4
    5     3    >   ECHO                                                     'is+set%0A'
    7     4    >   ASSIGN                                                   !1, null
    8     5        INIT_FCALL                                               'var_dump'
          6        TYPE_CHECK                                    2  ~6      !1
          7        SEND_VAL                                                 ~6
          8        DO_ICALL                                                 
    9     9        INIT_FCALL                                               'var_dump'
         10        TYPE_CHECK                                    2  ~8      !2
         11        SEND_VAL                                                 ~8
         12        DO_ICALL                                                 
         13      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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