Haskell Platform call for consensus: add transformers and revise the mtl package to depend on it

[Ross Paterson]

On Tue, Nov 02, 2010 at 02:17:03PM +0100, Johan Tibell wrote:
> This is a call for consensus for the following proposal:
> 
>     http://trac.haskell.org/haskell-platform/wiki/Proposals/transformers
> 
> Are there any unresolved concerns?

Brent Yorgey's report raises one: the following functions, defined in
the transformers package as replacements for data constructors for the
base monads, should probably be re-exported by the new mtl:

Control.Monad.Cont:
    cont :: ((a -> r) -> r) -> Cont r a
Control.Monad.RWS.Lazy:
    rws :: (r -> s -> (a, s, w)) -> RWS r w s a
Control.Monad.RWS.Strict:
    rws :: (r -> s -> (a, s, w)) -> RWS r w s a
Control.Monad.Reader:
    reader :: (r -> a) -> Reader r a
Control.Monad.State.Lazy:
    state :: (s -> (a, s)) -> State s a
Control.Monad.State.Strict:
    state :: (s -> (a, s)) -> State s a
Control.Monad.Writer.Lazy:
    writer :: (a, w) -> Writer w a
Control.Monad.Writer.Strict:
    writer :: (a, w) -> Writer w a