Re: ffmpeg documentation no longer builds after Texinfo 7.1 (due to --init-file=)

[Gavin Smith]

On Sat, Jan 27, 2024 at 04:26:10PM +0100, Patrice Dumas wrote:
> Hello,
> 
> On Sun, Nov 05, 2023 at 12:13:00PM +0100, Arsen Arsenović wrote:
> > 
> > Patrice Dumas <pertusus@free.fr> writes:
> > 
> > > my $texinfo_version = texinfo_get_conf('PACKAGE_VERSION');
> > > $texinfo_version =~ s/\+dev$//;
> > > # determine if texinfo is at least version 6.8
> > > my $program_version_num = version->declare($texinfo_version)->numify;
> > 
> > Oh, interesting.  On my system, I'm using texinfo built from master, and
> > it completely lacks PACKAGE_VERSION!  (if I rebuild from releases/7.1,
> > it's present).  It looks like it got removed in
> > 6a1a78b941a832033b8939ab4cdce1646dd56904.
> 
> I have added a new interface in the version in development to get the
> PACKAGE_VERSION and other PACKAGE* variables as set by configure:
> 
> my $texinfo_version = Texinfo::Common::get_constant('PACKAGE_AND_VERSION');
> 
> However, since you need to know the version to know if you can call that
> function, this is probably be useful for you only when you do not
> support versions older than the first version with that function anymore.

We should think carefully about the best interface for this as it is
breaking backwards compatibility again.  We should have a good interface
that we won't need to change in the future.  So I would not encourage
users of the interface to change their compatibility code until we have
finalised it.

The get_constant function has been recently added but I think the name of
this is too generic.  It's only seems to be used for version information.
Since the use of this is very limited, why not have special functions
like, for example, Texinfo::Common::get_version which don't take any
parameter?

I notice there is still use of PACKAGE_VERSION_OPTION in the source code.
Is your plan to replace this?

I don't know how ffmpeg or other packages are supposed to adapt to the
new interface.  Perhaps we could put special case code in get_conf to
check for "PACKAGE_VERSION" and redirect to the new interface?