The future of the Haskell98 and Haskell2010 packages

Richard Eisenberg eir at
Tue Nov 18 16:44:55 UTC 2014

I support this direction. But I disagree with one statement you've made:

On Nov 18, 2014, at 11:07 AM, Austin Seipp <austin at> wrote:
> To be clear: GHC can still typecheck, compile, and efficiently execute
> Haskell 2010 code. It is merely the distribution of compatible
> packages that has put us in something of a bind.

GHC 7.10 will not be able to compile a Haskell2010-compliant Monad instance. In fact, as far as I can see, there is no way to write a Monad instance that is both portable to other Haskell compilers and acceptable to GHC 7.10. I think this point should be included in the manual (if I'm right).

This makes me a little sad, but I don't disagree with any of the decisions we've made along the way.


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