gtk2hs-buildtools

[gitfoxi]

cabal install gtk2hs-buildtools
Resolving dependencies...
Notice: installing into a sandbox located at
/Users/mfox/stackage/.cabal-sandbox
Configuring gtk2hs-buildtools-0.13.0.3...
Failed to install gtk2hs-buildtools-0.13.0.3
Build log ( /Users/mfox/stackage/.cabal-sandbox/logs/gtk2hs-buildtools-0.13.0.3.log ):
Configuring gtk2hs-buildtools-0.13.0.3...
setup-Simple-Cabal-1.22.2.0-x86_64-osx-ghc-7.10.1: The program 'happy' version
>=1.18.9 is required but it could not be found.
cabal: Error: some packages failed to install:
gtk2hs-buildtools-0.13.0.3 failed during the configure step. The exception
was:
ExitFailure 1

If I first cabal install happy then it goes ahead just fine.

gtk2hs-buildtools.cabal has:

        build-tools:    alex >= 3.0.1, happy >= 1.18.9

And the nightly cabal config has:

             happy ==1.19.5,

Is it maybe a cabal problem? Cabal-install is (the one thing) installed outside the sandbox:

cabal-install version 1.22.4.0
using version 1.22.2.0 of the Cabal library

Should cabal-install also be installed inside the sandbox?

[snoyberg]

This is a long-standing limitation of cabal-install unfortunately, see haskell/cabal#220. The solution you found (manually running cabal install happy) is the correct one. I'm working on a different project that will fix this problem, and hopefully be announcing next week. But using the current tooling, there's nothing else we can do to fix it.

[snoyberg]

Note that stack now addresses this problem correctly and will install the correct build tool dependencies automatically.