Re: (featurep 'multi-tty) => t on Windows

[Juanma Barranquero]

On Sat, Dec 13, 2008 at 00:27, Eli Zaretskii <address@hidden> wrote:

> That's Emacs who evaluated the expression, not emacsclient, and doing
> something with that in normal emacsclient usage is impossible.  What I
> meant is that you users cannot tweak emacsclient to do something like
> "if this Emacs supports feature XYZ use option -N, otherwise use
> option -M" (although one could write a shell script to do that).
> emacsclient doesn't have an extension language that could make use of
> that paradigm.

I suppose a limited form of that wouldn't be too hard to implement, if
necessary.

> And btw, I don't think Emacs practice agrees with you in general: we
> have quite a few features that cannot be tested with featurep, because
> no code `provide'd them.  Just grep the Lisp sources for fboundp.

I know. But there's a difference between

   (if (fboundp 'whatever)
       (whatever ...))

and

  (if (fboundp 'whatever)
      (something-else...))

Checking for a function before using it is clean. Checking for a
function or a variable, as a way to know whether some "pack" of new
features are installed, is not. Now, I'm not proposing to start adding
features or subfeatures for the old code, of course. But it is at
least something to consider when adding big chunks of new
functionality.

    Juanma