FunctorM.fmapM vs. Traversable with GHC-6.4 and GHC-6.8

John Meacham john at
Wed Feb 20 23:44:33 EST 2008

On Thu, Feb 21, 2008 at 05:39:27AM +0100, Henning Thielemann wrote:
> What is the intended way to make a library using FunctorM/fmapM compatible
> to both GHC-6.4 and GHC-6.8 ?

Just a note, DrIFT 2.2.3 or later
( supports deriving both the
Foldable and Traversable classes for arbitrary types, this should
alleviate the migration issues somewhat.


John Meacham - ⑆⑆john⑈

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