[Haskell-cafe] Removing mtl from the Haskell Platform
wren ng thornton
wren at community.haskell.org
Thu May 14 18:18:20 EDT 2009
kahl at cas.mcmaster.ca wrote:
> 6) I haven't been able to pinpoint it in the Haddock docs,
> but somehow Control.Monad.State re-exports Control.Monad,
> which invalidates my explicit Control.Monad imports whenever I import
> Control.Monad.State full and unqualified
Many of the mtl modules do this, and I also find it irksome since it
means having a list of imports which all duplicate the same "hiding
(foo,bar,blatz)" annotation. Explicitly importing just the desired
functions mitigates this, but it's still a bad API choice.
> After all, I can use monads perferctly fine from the Prelude,
> but have to
> import Control.Monad (liftM)
> all the time anyway...
While we're on the topic ;) it'd be *really* nice if the Haskell'
Prelude exported MonadPlus along with the Monad stuff (or H' equivalents).
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