<?php
$rx = "~(?<!\\\\)(?:\\\\{2})*\(\?(?|P?<([_A-Za-z]\w{0,31})>|'([_A-Za-z]\w{0,31})')~";
$s = "(?P<name>\w+): (?<name2>\w+): (?'digit'\d+)";
PD9waHAKCiRyeCA9ICJ+KD88IVxcXFwpKD86XFxcXHsyfSkqXChcPyg/fFA/PChbX0EtWmEtel1cd3swLDMxfSk+fCcoW19BLVphLXpdXHd7MCwzMX0pJyl+IjsKJHMgPSAiKD9QPG5hbWU+XHcrKTogKD88bmFtZTI+XHcrKTogKD8nZGlnaXQnXGQrKSI7CnByZWdfbWF0Y2hfYWxsKCRyeCwgJHMsICRyZXMpOwpwcmludF9yKCRyZXNbMV0pOw==