Compile failure with GHC 7.8 and older

Question

Compile failure with GHC 7.8 and older

hvr opened this issue 8 years ago · 2 comments

See below

Configuring component lib from cabal-file-th-0.2.4
Preprocessing library cabal-file-th-0.2.4...
[1 of 1] Compiling Distribution.PackageDescription.TH ( Distribution/PackageDescription/TH.hs, /tmp/matrix-worker/1480465990/dist-newstyle/build/x86_64-linux/ghc-7.8.4/cabal-file-th-0.2.4/build/Distribution/PackageDescription/TH.o )

Distribution/PackageDescription/TH.hs:34:21:
    Not in scope: ‘<$>’
    Perhaps you meant one of these:
      ‘<>’ (imported from Text.PrettyPrint),
      ‘<+>’ (imported from Text.PrettyPrint)

Answer 1 · 2016-11-30T22:47:14.000Z

I don't have 7.8 around to test with, but I've replaced the <$> with fmap. Is all that's needed?

Answer 2 · 2016-12-01T07:50:12.000Z

@nkpart may I suggest giving

https://github.com/hvr/multi-ghc-travis/blob/master/make_travis_yml_2.hs

a try? That way you can detect early on (without having to install GHC 7.8 locally) when something breaks with the set of GHC versions you want to support.