3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump(preg_match('/^\b([a-z0-9] ?)+$\b/i', 'this works'), preg_match('/^\b([a-z0-9] ?)+$\b/i', 'this should not work'));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/T9qQ5
function name:  (null)
number of ops:  13
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    1     0  E >   INIT_FCALL                                               'var_dump'
          1        INIT_FCALL                                               'preg_match'
          2        SEND_VAL                                                 '%2F%5E%5Cb%28%5Ba-z0-9%5D+%3F%29%2B%24%5Cb%2Fi'
          3        SEND_VAL                                                 'this+works'
          4        DO_ICALL                                         $0      
          5        SEND_VAR                                                 $0
          6        INIT_FCALL                                               'preg_match'
          7        SEND_VAL                                                 '%2F%5E%5Cb%28%5Ba-z0-9%5D+%3F%29%2B%24%5Cb%2Fi'
          8        SEND_VAL                                                 'this+should+not++work'
          9        DO_ICALL                                         $1      
         10        SEND_VAR                                                 $1
         11        DO_ICALL                                                 
         12      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


preferences:
153.04 ms | 1398 KiB | 17 Q