Bug#527917: please break circular dependency

[Brendan O'Dea]

On Sat, May 9, 2009 at 10:16 PM, Holger Levsen <holger at layer-acht.org> wrote:
> Whats wrong with making perl depend perl-modules and making perl-modules only
> recommend perl? (I do the same with the tuxtype and tuxtype-data packages,
> and tuxtype-data is also basically useless without tuxtype. You could look at
> the images, yeah ;-)

The co-dependency between perl and perl-modules is required as these
are fundamentally one package, split only into arch any/all parts.
Modules within perl use modules within perl-modules and vice-versa.

Ideally the dependency would simply be expressed as a perl dependency
of the exact version on perl-modules (as is done for perl-base), and
this was originally how the package was set up.

This caused issues in unstable where the package became uninstallable
when a new version was available on one arch, but not built yet for
others and at the request of porters I changed the dependencies to be
looser allowing a newer version of perl-modules to be installed.  An
inverse dependency is now required however, as otherwise perl 5.6.1-1
is satisfied with perl-modules 5.10.0-22 .

Additionally these dependencies must be modified if a file moves
between the packages, an example may be seen in the changelog for
5.8.8-9 and in #377385: without the dependency changes it became
possible to have versions of perl and perl-base installed, neither of
which contained a module which had moved (similar issues occur when
moving modules to/from perl-base).

So in summary while it may not be ideal to have such package
interdependencies, these are used achieve clearly defined requirements
and are not arbitrary.  Additionally, it would seem to work: perl has
been successfully installed and upgraded  innumerable times over the
years since this dependency was introduced.

Unless there is an actual, demonstrable problem with the current
versions of perl, apt and dpkg I would suggest either closing this bug
or at least downgrading to wishlist.

--bod