Re: Liberalising IncoherentInstances

2013-08-19 Thread Joachim Breitner
Hi, Am Montag, den 19.08.2013, 08:27 + schrieb Simon Peyton-Jones: > Yes that makes sense to me. Please do document the reasoning of this thread > (and the example you give) in a "Note [Incoherent instances]" somewhere > though! done, patches ready for review and merge at https://github.co

RE: Marking type constructor arguments as nominal (e.g. Set)

2013-08-19 Thread Simon Peyton-Jones
Correct. For the "newtype wrapper" stuff you could simply omit a "deriving( NT )" on Set. But the role annotation *also* prevents bogus newtype-deriving, as you are pointing out. Eg class C a where foo :: Set a -> a instance C Int where ... newtype Age = MkA

RE: Liberalising IncoherentInstances

2013-08-19 Thread Simon Peyton-Jones
Yes that makes sense to me. Please do document the reasoning of this thread (and the example you give) in a "Note [Incoherent instances]" somewhere though! S | -Original Message- | From: Glasgow-haskell-users [mailto:glasgow-haskell-users- | boun...@haskell.org] On Behalf Of Joachim Bre

Re: Liberalising IncoherentInstances

2013-08-19 Thread Joachim Breitner
Good morning, Am Samstag, den 27.07.2013, 20:16 + schrieb Simon Peyton-Jones: > So the change I propose to make IncoherentInstances to pick > arbitrarily among instances that match. More precisely, when trying > to find an instance matching a target constraint (C tys), > > a) Find all instan

Question about `compileToCoreModule`

2013-08-19 Thread Daniel F
Hi, everyone, I have a question about `compileToCoreModule` function from the GHC module. I noticed that the following code not just outputs the Core code, but also produces object files and a linked executable (in case when 'test.hs' is a program): --- module Main where