Re: Improving in-place upgrades of Ada packages from Lenny to Squeeze

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

David Kalnischkies wrote:
> The only thing i can see from this "hint" is that dependencies are
> missing. Fine, i guess i have talked about nothing else so far.
> Whatever causes the removal of gnat-4.3 can e.g. also "Breaks"
> all the packages who missed proper dependencies before.

(side note: I've been a Debian developer since before Breaks:
even existed, so I was unaware of its presence until this
thread.  This may be what I was looking for all along.)

OK. After reading Policy about Breaks, I'm still not entirely sure
how to best apply it.  Maybe you can enlighten me.  I am thinking
of two options; maybe there is a third one that eludes me ATM.

Option 1: upload a new package "gnat" that Breaks: all -dev packages
that were present in Lenny but are no longer present in Squeeze.
This however does not really help apt, or the user, discover the
new replacement packages.

Option 2: change each new -dev package so that it Breaks: its
predecessor.  For example, let libgtkada2.14.2-dev Break:
libgtkada2.8.1-dev.

Question 1: which option do you think is best? (my guess is option 2).

Question 2: if I add Breaks: to a -dev package, which ones of
Conflicts: and Replaces: should I also specify? (currently, both
are specified; the new packages replace almost all files of the
old packages).  The goal is, of course, to make unattended upgrades
that delete the old -dev packages and install the new ones possible.

Thanks for any help.

-- 
Ludovic Brenta.