The transformers package

[Tags:bsd3, library]

A portable library of functor and monad transformers, inspired by the paper "Functional Programming with Overloading and Higher-Order Polymorphism", by Mark P Jones, in Advanced School of Functional Programming, 1995 (

This package contains:

The package can be used on its own in portable Haskell code, in which case operations need to be manually lifted through transformer stacks (see Control.Monad.Trans.Class for some examples). Alternatively, it can be used with the non-portable monad classes in the mtl or monads-tf packages, which automatically lift operations introduced by monad transformers through other transformers.


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Change log changelog
Dependencies base (>=2 && <4.9) [details]
License BSD3
Author Andy Gill, Ross Paterson
Maintainer Ross Paterson <>
Category Control
Source repository head: darcs get
Uploaded Mon Nov 10 13:16:30 UTC 2014 by RossPaterson
Updated Mon Dec 21 07:35:26 UTC 2015 by HerbertValerioRiedel to revision 1
Distributions Arch:, Debian:, Fedora:, LTSHaskell:, NixOS:, Stackage:
Downloads 256319 total (10514 in the last 30 days)
2 []
Status Docs uploaded by user
Build status unknown [no reports yet]
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