RE: next emacs version?

[Drew Adams]

> > What will the next Emacs version be?
> 
> 23.2

Confirms what I thought.

> > 24.0.50.1
> > But I thought the next release would be Emacs 23.2, not 24.
> 
> That's not a contradiction.  Emacs 23.2 will be delivered from a
> branch, not from the trunk.  Version 24.0.50 is from the development
> trunk.

Also confirms what I thought. Thanks.

> > What is the proper test (or a reasonable test) to use in the
> > code, for this change? It's OK if I don't support the change
> > until the release is out. It's the test for the
> > official release I'm most interested in. (But I'm also 
> > interested in advice about testing against an in-development version.)
> 
> If you want to discern v23.x from v24.x, emacs-major-version is the
> first thing I'd try.

I said I want to discern this code change, which will be made by Emacs Dev to
23.2 (probably; it is made now in 24.0.50.1). So `emacs-major-version' is not
the way to check that.

In the past, I've checked `emacs-major-version' and `emacs-minor-version'
together, or I've checked for the change using string-match with
`emacs-version'. I was wondering if there is a recommendation here.

And I was wondering if there isn't a simple check that will match anything more
recent than the release 23.1. That is, including the dev version 24.0.50.1 and
the next release, 23.2. That's a typical use case for me: Emacs Dev has changed
something after the last release and I expect that the change will remain in
place for the new release. 

Yes, obviously, if the change is in fact removed before the new release then my
test will no longer be accurate. But that's the minority of such cases, in my
experience, and I can live with that maintenance problem.

Obviously, if there is a more pertinent test such as a new variable or function,
I use that instead. But this example is pretty typical of the problem. The value
of a regexp variable has changed, and that changes the behavior of the code. I
need to test which regexp value is in use, the old one or the new one.

FWIW, the regexp in question, `directory-listing-before-filename-regexp', is
among the hairiest I've come across (have a look - quite amusing), and I don't
think it's a good idea to try to test against that value. I see no alternative
but to test the Emacs version. (This affects Dired font-locking. The new value
of the regexp adds a level of group nesting.)