Has anyone ever encountered a Monad Transformer in the wild?

Posted by martingw on Stack Overflow See other posts from Stack Overflow or by martingw
Published on 2010-05-03T17:37:23Z Indexed on 2010/05/03 19:28 UTC
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haskell

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monad-transformers

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design-patterns

In my area of business - back office IT for a financial institution - it is very common for a software component to carry a global configuration around, to log it's progress, to have some kind of error handling / computation short circuit... Things that can be modelled nicely by Reader-, Writer-, Maybe-monads and the like in Haskell and composed together with monad transformers.

But there seem to some drawbacks: The concept behind monad transformers is quite tricky and hard to understand, monad transformers lead to very complex type signatures, and they inflict some performance penalty.

So I'm wondering: Are monad transformers best practice when dealing with those common tasks mentioned above?

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