3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php preg_match('/^[\d]$/', '1000', $matches); print_r ($matches);
Finding entry points
Branch analysis from position: 0
Jump found. Position 1 = -2
filename:       /in/FAAkL
function name:  (null)
number of ops:  9
compiled vars:  !0 = $matches
line     #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
   2     0  E >   INIT_FCALL                                               'preg_match'
         1        SEND_VAL                                                 '%2F%5E%5B%5Cd%5D%24%2F'
         2        SEND_VAL                                                 '1000'
         3        SEND_REF                                                 !0
         4        DO_ICALL                                                 
   3     5        INIT_FCALL                                               'print_r'
         6        SEND_VAR                                                 !0
         7        DO_ICALL                                                 
         8      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 7.2.0