Re: debian control file out of date? was: Re: live cd-with lilypondhttp://lilypond.org/doc/v2.10/Documentation/topdocs/INSTALL

[Thomas Bushnell BSG]

On Sat, 2008-08-30 at 22:16 +0100, Rob Canning wrote:
> the debian package lilypond-data has a pre-depend of  texlive  though 
> lilypond  no longer has a runtime dependency on tex
> this is because as thomas explained :
> 
> > When the package is upgraded, the old
> > automatically generated fonts need to be cleaned up, and we are using
> > kpsewhich to find them in order to delete them.
> 
> i dont fully understand why this is a pre-depend and not a build-depend

It has nothing to do with building.

1) User installs old lilypond.
2) User uses old lilypond, causing the automatic generation of font
files.
3) User installs new lilypond.

Step (3) must delete the now out-of-date fontfiles generated in step
(2).  kpsewhich is being used to locate those files.

> when are these fonts generated? during runtime or buildtime? is it not
> the job of the old lilypond-data to cleanup after itself rather than the
> new version doing the clean up?

Surely true, and indeed it does.  Of course, it needs to know where the
automatically generated files are located.  It uses kpsewhich to find
them. 

> are the consequences of not cleaning these files up significant compared
> with the implications of relying on what should no longer be a dependency.

Yes.  Because the files are still hanging around, failure to clean them
produces bugs.  People will expect to get the latest feta fonts--which
change from version to version--and they won't if the old out-of-date
files don't get deleted.

And, let's keep in mind here: the target case you are thinking of
matters a lot to you, but a lot less in the grand scheme of things.

Thomas