Typechecker plugins and 7.10

Eric Seidel eric at seidel.io
Fri Dec 12 17:14:14 UTC 2014

I agree, marking type-checker plugins as experimental and subject to
change makes perfect sense given how little experience we have writing
them at the moment.


Richard Eisenberg <eir at cis.upenn.edu> writes:

> As I'm referenced here, I'll speak up: yes, I think we should advertise that the
> plugin interface is purely a technology preview, and very subject to change. I'm
> sure that as users adopt this powerful new feature, they and we will discover
> ways that it could be improved, or perhaps ways that it can subvert GHC, or
> etc. In order to have a tighter feedback loop between devs and users, I think
> that updating this part of GHC between minor releases is appropriate, for the
> 7.10 cycle. Hopefully, a year from now, we'll be ready to stabilize and then
> offer a more concrete implementation for 7.12.
> Of course, I'm curious to hear others' opinions on this!
> Thanks,
> Richard
> On Dec 12, 2014, at 3:50 AM, Adam Gundry <adam at well-typed.com> wrote:
>> Hi Austin, devs,
>> I'm not sure what stage the 7.10 branch split and RC have got to, but if
>> possible I'd like to get Phab:D553 included (my special pleading is that
>> it makes relatively small, self-contained changes that will make it
>> slightly harder to shoot oneself in the foot when writing a plugin). I
>> realise you have to say "no" at some point though!
>> More generally, at Richard's suggestion I propose that (at least for
>> 7.10) we explicitly make no guarantees about the stability of the
>> TcPluginM API, and advertise that we may choose to make breaking changes
>> between minor GHC releases. After all, this feature is highly
>> experimental and tightly coupled to GHC itself.
>> All the best,
>> Adam
>> -- 
>> Adam Gundry, Haskell Consultant
>> Well-Typed LLP, http://www.well-typed.com/
>> _______________________________________________
>> ghc-devs mailing list
>> ghc-devs at haskell.org
>> http://www.haskell.org/mailman/listinfo/ghc-devs
> _______________________________________________
> ghc-devs mailing list
> ghc-devs at haskell.org
> http://www.haskell.org/mailman/listinfo/ghc-devs

More information about the ghc-devs mailing list