Re: intern-soft, find-face/get-face, and facep for determining faces' definedness

["Stephen J. Turnbull" <stephen@xemacs.org>]

>>>>> "Zajcev" == Zajcev Evgeny <zevlg@yandex.ru> writes:

    Zajcev> Andreas Schwab <schwab@suse.de> writes:

    >> Zajcev Evgeny <zevlg@yandex.ru> writes:

    >>> Most of functions that deal with faces should use `(facep
    >>> (get-face <face>))' sexp to check face validity.

    >> Why do you need facep if get-face already did all validation?

XEmacs doesn't need facep.  facep is useful in very few contexts, and
this isn't one of them.

    Zajcev> Oh yes, it should be one of: `(get-face <face>)' or
    Zajcev> `(facep (find-face <face>))' to avoid signals.

In XEmacs (facep (find-face ...)) is redundant.  It merely turns a
useful value (a face, which is just as true as t) into t.

There's no theoretical reason why would we couldn't sync to the Emacs
API, with faces being symbols registered as faces, no more and no
less.  However, in practice verifying it does no harm would be a lot
of work, and I don't see a benefit to it.  OTOH, adding the find-face
API to Emacs is trivial and can't do harm to existing code, although
it's really not necessary at all in Emacs AFAICS.  It's a minor
convenience in the code the OP posted, of course, but you could just
as easily inline Miles's implementation.

I don't see need for further discussion of XEmacs APIs on emacs-devel,
and I know y'all are quite busy right now.  So this is my last post in
this thread to emacs-devel (although I will continue to monitor it).
I will respond to further posts as appropriate, but (unless requested)
only on xemacs-beta.

Regards,

-- 
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