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<?php $regex = '(^([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*|\0\\\\\0)$)'; $classes = [ 'foo', 'foo\\bar', 'foo\\bar\\baz', ]; foreach ($classes as $class) { var_dump(preg_match($regex, $class)); }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 77) Position 1 = 3, Position 2 = 12
Branch analysis from position: 3
2 jumps found. (Code = 78) Position 1 = 4, Position 2 = 12
Branch analysis from position: 4
1 jumps found. (Code = 42) Position 1 = 3
Branch analysis from position: 3
Branch analysis from position: 12
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 12
filename:       /in/80YSU
function name:  (null)
number of ops:  14
compiled vars:  !0 = $regex, !1 = $classes, !2 = $class
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%28%5E%28%5Ba-zA-Z_%5Cx7f-%5Cxff%5D%5Ba-zA-Z0-9_%5Cx7f-%5Cxff%5D%2A%7C%5C0%5C%5C%5C0%29%24%29'
    5     1        ASSIGN                                                   !1, <array>
   11     2      > FE_RESET_R                                       $5      !1, ->12
          3    > > FE_FETCH_R                                               $5, !2, ->12
   12     4    >   INIT_FCALL                                               'var_dump'
          5        INIT_FCALL                                               'preg_match'
          6        SEND_VAR                                                 !0
          7        SEND_VAR                                                 !2
          8        DO_ICALL                                         $6      
          9        SEND_VAR                                                 $6
         10        DO_ICALL                                                 
   11    11      > JMP                                                      ->3
         12    >   FE_FREE                                                  $5
   13    13      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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