bug#54296: Add buffer-matching functionality

[Eli Zaretskii]

> Date: Tue, 14 Jun 2022 22:00:20 +0300
> Cc: 54296@debbugs.gnu.org, philipk@posteo.net, larsi@gnus.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> 
> > And if I understand your reasoning above, then doesn't
> > 
> >    (eq major-mode 'fundamental-mode)
> > 
> > provide an easy default that can be read at a glance?
> 
> Are you proposing adding a "keyword" 'eq' which would have a variable 
> name as its first arg and the value as its second arg?

No, I proposed to use the "predicate function" method (which already
exists).