[Haskell-cafe] Re: Transformers versus monadLib versus...
limestrael at gmail.com
Tue Jul 6 09:29:07 EDT 2010
Yes but, for instance, every library which provides monad transformers will
provides a MTL's MonadTrans instance, not a monadLib's MonadT instance.
And since a library hides its types internals, you cannot write the MonadT
For instance, I was planning to translate a little program of mine (which
uses quite heavily monad transformers) to monadLib. It uses the packages
operational which is based on MTL, and I cannot make myself operational's
transformers instances of MonadT.
How would you solve that?
(btw, I like the fact that monadLib provides IdT ^^ (IdentityT))
2010/7/6 Ertugrul Soeylemez <es at ertes.de>
> Yves Parès <limestrael at gmail.com> wrote:
> > monadLib looks nice, indeed, but the major problem with using it
> > resides in the fact that most of the libraries on hackage use MTL.
> > Must be tedious to have to use two monad libraries at the same time...
> In general this is a minor problem. Note that when using a monad from
> another library usually you get provided with a type alias (or even a
> newtype) and a number of convenience functions, so you don't have to
> access names from both libraries at the same time.
> I can only speak for myself, but I've never had a problem with this,
> even though my packages often have lots and lots of dependencies.
> nightmare = unsafePerformIO (getWrongWife >>= sex)
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Haskell-Cafe