[Xotcl] nx attribute predefined value constrains, two more possible options?

From: Victor Mayevski <vitick_at_gmail.com>
Date: Tue, 26 Oct 2010 13:58:45 -0700 (PDT)

How about adding two move predefined constrains?:

:attribute a:regexp={myregexp}
:attribute a:glob={myglob}

Thanks