Should the PVP be changed with regards to instances?

[Jeremy Shaw]

Their code breaking is punishment for creating an orphan instance
instead of sending a patch upstream ;)

In theory.. practically speaking that is not always practical to wait
for an upstream maintainer to maybe take your patch to add new
instances.

I have never bumped the major version number just because I added a
new instance. So, I guess I am in favor of making the bump a
'suggests' instead of 'requires'.

When I bump the major version on something like happstack-server. I
then have to update half a dozen other packages to reflect the new
version number. And I have to email maintainers of packages like
digestive-functors, gitit, etc and tell them to bump their version
numbers. Additionally, people packaging happstack for a linux
distribution now have to also update a bunch of packages instead of
just happstack-server. So, that is a lot of work for myself and
others, in the off chance that somebody created an orphan instance.

In theory, bumping the major version sounds like the right thing to
do. But pragmatically.. it is a bit of a burden sometimes. Especially
when compared to the risk of something actually going wrong.

- jeremy



On Tue, Dec 20, 2011 at 10:32 AM, Ross Paterson <ross at soi.city.ac.uk> wrote:
> On Tue, Dec 20, 2011 at 04:12:32PM +0000, Johan Tibell wrote:
>> Introducing new instances is unlikely to break users, as they will only get
>> into trouble if they use orphan instances, which is already asking for trouble!
>
> I don't like orphan instances either, but users often do define instances
> they perceive as missing.
>
> _______________________________________________
> Libraries mailing list
> Libraries at haskell.org
> http://www.haskell.org/mailman/listinfo/libraries