transformers: Concrete functor and monad transformers

[ bsd3, control, library ] [ Propose Tags ]
Versions,,,,,,,,,,,,,,,,,,,,,,,, (info)
Dependencies base (>=1.0 && <4.8), special‑functors (==1.0.*) [details]
License BSD-3-Clause
Author Andy Gill, Ross Paterson
Maintainer Ross Paterson <>
Revised Revision 1 made by HerbertValerioRiedel at Thu Dec 4 13:57:37 UTC 2014
Category Control
Uploaded by RossPaterson at Wed Oct 16 07:30:45 UTC 2013
Distributions Arch:, Debian:, LTSHaskell:, NixOS:, Stackage:
Downloads 302608 total (498 in the last 30 days)
Rating 2.5 (votes: 4) [estimated by rule of succession]
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Status Docs available [build log]
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Haskell 98 part of a monad transformer library, inspired by the paper "Functional Programming with Overloading and Higher-Order Polymorphism", by Mark P Jones, in Advanced School of Functional Programming, 1995 (

This part contains the monad transformer class, the concrete monad transformers, operations and liftings. It can be used on its own in Haskell 98 code, or with the monad classes in the monads-fd or monads-tf packages, which automatically lift operations introduced by monad transformers through other transformers.





Choose the newer base package, including Applicative and other Functor classes.


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