Proposal: Slim base-5 API package

Joachim Breitner mail at
Wed Jul 17 10:28:45 CEST 2013


Am Mittwoch, den 17.07.2013, 09:46 +0200 schrieb Henning Thielemann:
> On Wed, 17 Jul 2013, Bardur Arantsson wrote:
> > On 2013-07-16 23:45, Henning Thielemann wrote:
> >>
> >> I think his wish was to ensure that e.g. 'map' has the same type in GHC,
> >> fay, JHC and others, although it might be implemented differently (with
> >> foldr/build, or stream-fusion, or whatever).
> >
> > Exactly!
> >
> > (But perhaps I'm just a natural pessimist -- it may not matter much in
> > practice.)
> I guess that it can happen easily, that a function type has different 
> class constraints based on the implementation. A type enforced by the 
> 'base' package would avoid that people rely on weak constraints of a 
> certain implementation.

there won’t be many base re-implementations, and these will be carefully
crafted. I’d leave it to those people to pay attention to these details,
without over-engineering a technical solution.

It should be easily to whack up a script that extracts the API of a
package (e.g. a list of modules and their contents); just run in on both
implementations and diff them. In fact, I think I saw someone create
such a tool already; I just don’t remember who or where.

If you want to make it more formal, we can put this file somewhere as a


Joachim “nomeata” Breitner
  mail at joachim-breitner.de
  Jabber: nomeata at  • GPG-Key: 0x4743206C
  Debian Developer: nomeata at
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