On Thu, Mar 02, 2006 at 01:10:42PM +0000, Ross Paterson wrote:
On Thu, Mar 02, 2006 at 05:02:39AM -0800, John Meacham wrote:
On Thu, Mar 02, 2006 at 12:41:22PM +0000, Ross Paterson wrote:
I propose to deprecate Data.FunctorM in favour of Data.Traversable:
I have no particular objection, The applicative stuff looks interesting, though I have not explored it too much.
my only request is that we add 'mapM_' and 'sequence_' to the traversable class, there are many monads for which they are vital for controlling space leaks.
They're in Data.Foldable, though not as class methods:
http://www.haskell.org/ghc/dist/current/docs/libraries/base/Data-Foldable.ht...
e.g. Set is an instance of Foldable but not Traversable.
They should definitly be made class methods somewhere. They usually have to be custom written for a given datatype and RULES pragmas arn't powerful enough to know when somethings monadic result is not used. John -- John Meacham - ⑆repetae.net⑆john⑈