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

Bulat Ziganshin bulat.ziganshin at
Thu Feb 21 05:12:59 EST 2008

Hello Henning,

Thursday, February 21, 2008, 7:39:27 AM, you wrote:

> What is the intended way to make a library using FunctorM/fmapM compatible
> to both GHC-6.4 and GHC-6.8 ?

1) support two different cabal files and propose users to manually
rename one they need to .cabal
2) suggest 6.4 users to switch to newest cabal version which supports
config sections and use them
3) install library via makefile, custom haskell script or smth like

you also can combine these ideas :)

the more interesting question "how to provide compatibility with 7.0,
7.2 and other future ghc versions" :D

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at

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