Thanks Michael, So the user should use `cabal install --flags -ghc7 package-name` to install the package, if I'm not mistaken?
Will it work if the package is installed as a dependency? Will the flag environment be passed down from the root package? Is there a way to detect GHC version automatically? : ) Best, On Sun, Nov 28, 2010 at 1:32 AM, Michael Snoyman <[email protected]> wrote: > On Sat, Nov 27, 2010 at 6:59 PM, Jinjing Wang <[email protected]> wrote: >> Dear list, >> >> >From ghc 7.0.1 release notes: >> >>> The Language.Haskell.TH.Quote.QuasiQuoter type has two new fields: >>> quoteType and quoteDec. >> >> Some of my code needs to be conditionally compiled to support both >> version 6 and 7, what is the recommended way to do it? >> >> ref: >> >> * >> http://new-www.haskell.org/ghc/docs/7.0.1/html/users_guide/release-7-0-1.html > > Hi Jinjing, > > I've done this in Yesod. I'm not sure if it's the best way, but > basically I've added a ghc7 flag to the cabal file, and a block for > the library that reads: > > if flag(ghc7) > build-depends: base >= 4.3 && < 5 > cpp-options: -DGHC7 > else > build-depends: base >= 4 && < 4.3 > > Then whenever I want to quasi-quote in the code, I write: > > #if GHC7 > [quasiquoter| > #else > [$quasiquoter| > #endif > > Michael > -- jinjing _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
