Wow, I totally forgot about "if impl(ghc>=7.8)". That's the way to go of course! On Thu, Sep 11, 2014 at 12:04 AM, Herbert Valerio Riedel

wrote:

On 2014-09-10 at 20:41:27 +0200, Adam Bergmark wrote:

...

Hi Mike, something like this should do the trick (untested):

``` flag ghc78 description: Using GHC >= 7.8 default: True

library if flag(ghc78) build-depends: base >= 4.7 bedandbreakfast >= 5 else build-depends: base < 4.7 bedandbreakfast >= 4 ```

This uses a non-manual flag so cabal will toggle it if it needs to.

btw, why not simply use a "if impl(ghc>=7.8)" conditional w/o resorting to flags?