pure logger typeclass and monad transformer; documentation

 This package provides a typeclass for logging in pure code, or more generally,
 in any kind of context. You can do whatever you want with logs, especially get
 them, clear them or even sink them through 'IO' if you're logging in MonadIO.
 .
 This package provides the documentation for a library for the Haskell
 programming language.
 See http://www.haskell.org/ for more information on Haskell.