Bug#580034: perl: module deprecations in 5.12.0

[Dominic Hargreaves]

On Mon, May 03, 2010 at 12:26:43PM +0300, Niko Tyni wrote:
> We need to decide what to do with the module deprecations in 5.12.0.
> 
>  $ perl -w -e 'use Class::ISA'
>  Class::ISA will be removed from the Perl core distribution in the next major release. Please install it from CPAN. It is being used at -e, line 1.
> 
> The modules being deprecated from the core are (from perl5120delta.pod):
> 
>  Class::ISA
>  Pod::Plainer
>  Shell
>  Switch
> 
> Clearly these need to be packaged separately sooner or later.
> 
> The options I see are
> 
> A. Patch away the warning and do nothing until the modules are actually
>    removed in 5.14.0. At that point, add dependencies or recommendations
>    for the removed modules.
> 
> B. Package the modules separately now, recommend the new packages and patch
>    the warning to direct to apt instead of CPAN. Downgrade to suggestions
>    after one release cycle.
> 
> C. Package the modules separately now, depend on the new packages and don't
>    install the core versions in the binary packages at all. Downgrade to
>    recommendations or even suggestions after one release cycle.
> 
> I'm leaning towards C but B seems also like a good choice.  As I see it:
> 
> A is just postponing the issue for no clear benefit.
> 
> B is closest to the upstream way but has the drawback of needing two
> copies of the deprecated code.
> 
> C fixes this and offers a slightly smoother transition for people ignoring
> recommendations.  However, like A it postpones any breakage until later,
> possibly creating confusion because our deprecation schedule differs
> from the upstream one.
> 
> Input would be welcome.

I think I prefer B - it should make the transition less painful in the
long run.

We should also try and file bugs against packages using these modules,
if we can, once the separate packages are available.
 
> The separate packages would naturally fit with the pkg-perl group. I'd be glad
> if somebody would like to help and package them.

I'll look at doing that today.

-- 
Dominic Hargreaves | http://www.larted.org.uk/~dom/
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