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<?php $r1 = '/(?!<r)rn/'; $r2 = '(r(?:r(*SKIP)(*FAIL)|)n)'; var_dump(preg_match($r1, "rrn", $m1), $m1); var_dump(preg_match($r2, "rrn", $m2), $m2);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/DWLbU
function name:  (null)
number of ops:  21
compiled vars:  !0 = $r1, !1 = $r2, !2 = $m1, !3 = $m2
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '%2F%28%3F%21%3Cr%29rn%2F'
    4     1        ASSIGN                                                   !1, '%28r%28%3F%3Ar%28%2ASKIP%29%28%2AFAIL%29%7C%29n%29'
    6     2        INIT_FCALL                                               'var_dump'
          3        INIT_FCALL                                               'preg_match'
          4        SEND_VAR                                                 !0
          5        SEND_VAL                                                 'rrn'
          6        SEND_REF                                                 !2
          7        DO_ICALL                                         $6      
          8        SEND_VAR                                                 $6
          9        SEND_VAR                                                 !2
         10        DO_ICALL                                                 
    7    11        INIT_FCALL                                               'var_dump'
         12        INIT_FCALL                                               'preg_match'
         13        SEND_VAR                                                 !1
         14        SEND_VAL                                                 'rrn'
         15        SEND_REF                                                 !3
         16        DO_ICALL                                         $8      
         17        SEND_VAR                                                 $8
         18        SEND_VAR                                                 !3
         19        DO_ICALL                                                 
         20      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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