Re: heads-up: Haskell updates

[Ricardo Wurmus]

Timothy Sample <address@hidden> writes:

> Ricardo Wurmus <address@hidden> writes:
>
>> I think that’s a misunderstanding.  The cause for the error is earlier
>> when it complains that some packages depend on different versions of the
>> “transformers” package.  “StateT” is a monad transformer.
>
> For what it’s worth, I fixed this error on my machine by adding
> “ghc-transformers” as an input to “ghc-transformers-compat”.  (This also
> fixed “ghc-adjunctions”.)  This suggests to me that what you wrote
> earlier accounts for the problem:
>
>> * many problems are caused by the fact that GHC includes a bunch of
>>   packages that really shouldn’t be overridden by packages.  Examples
>>   are ghc-directory, ghc-binary, ghc-bytestring, etc.  Since we still
>>   have packages where these inputs are used, there can be conflicts down
>>   the line, which are hard to fix.

The solution might be to remove ghc-transformers from all packages that
currently have it as an input rather than add it wherever the
transformers is required.  This seems to be only ghc-mtl.  I’ve removed
it and am building ghc-mtl and ghc-resourcet now.

--
Ricardo

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