[Haskell-cafe] ANN: haskeline-class

Antoine Latter aslatter at gmail.com
Sat Jun 20 18:20:16 EDT 2009

I'd like to announce a small library newly on hackage:


Haskeline is an easy to use library, with a reasonable interface. The
one quirk that got in my way was that its 'InputT' monad transformer
defined its own instance of MonadState which allowed the user of the
library to peer into the guts of Haskeline. What I really wanted at
the time was an instance of MonadState which lifted the class
operations to an inner monad.

So I wrote a small newtype wrapper and a support class to work around
this. If anyone else has the same issue, the code is now on Hackage.

I've heard that this won't even be needed in the next major release of
Haskeline, but I'll likely keep this package up-to-date if anyone
finds the MonadHaskeline class useful.


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