cabal

I'm installing Haskell on Windows based on the instructions at https://www.haskell.org/platform/ and looking at step 3, it says, Modify your cabal config file (you can verify the location by running "cabal user-config init") to contain the following lines: extra-prog-path: C:\Program Files\Haskell Platform\8.0.2\msys\usr\bin extra-lib-dirs: C:\Program Files\Haskell Platform\8.0.2\mingw\lib extra-include-dirs: C:\Program Files\Haskell Platform\8.0.2\mingw\include But the auto generated config file contains e.g. extra-prog-path: C:\Users\w\AppData\Roaming\cabal\bin So that's a different value

$ cabal install arithmoi-0.4.0.3 results in multiple errors like: Math/NumberTheory/Moduli.hs:489:4: error: invalid preprocessing directive #-} ^ My System: OSX Mavericks Cabal version = 1.18.1.1 GHCI version = 7.6.3 Thanks in advance! Possible workaround here . xCode 5 comes with clang as c/c++/obj-c compiler. Haskell Platform is not ready for that. The next ghc release will fix that. Also see here . 来源： https://stackoverflow.com/questions/19597324/cabal-error-invalid-preprocessing-directive

I'm trying to build xmonad in Mountain Lion to run with Xquartz 2.7.2, tutorial found here . I'm using cabal to get required X11 libraries cabal install X11-1.5.0.1 . That didn't work, so I got the tar and tried building it with ghc, same error. It won't configure: Resolving dependencies... Configuring X11-1.5.0.1... configure: WARNING: unrecognized options: --with-compiler, --with-gcc checking for gcc... gcc checking whether the C compiler works... yes checking for C compiler default output file name... a.outchecking for suffix of executables... checking whether we are cross compiling... no

How does dependency hell happen in Cabal-install? I read the following at Cabal/Survival - HaskellWiki : 1. What is the difficulty caused by Cabal-install? The main difficulty with Cabal is otherwise known as 'dependency hell', in which the cabal-install does not manage to install a desired package for a reason or another, leading to large amount of manual work. As an example of this difficulty, consider a case where the user wishes to install packages A and B. Both of these work with package C, but not with the same version of C. I understand why this would make sense generally, but not with

I got both ghc6 and ghc7 on my desktop. To install new packages (for the specific ghc version), I use cabal with the flag --with-compiler=<ghc-dir> to specify for which ghc i want the package installed. I do cabal update before installing any new package. But how to I specify for which ghc I want the update? I mean, there is no --with-compiler flag as with cabal install . I would think that just like I use ghc-pkg7 for ghc7, there would be cabal7 . Apart from the cabal install command which I know to which ghc version it is applying, I don't know which ghc is affected with the other cabal

Configuring cairo-0.12.0... setup.exe: The program pkg-config version >=0.9.0 is required but it could not be found. cabal: Error: some packages failed to install: cairo-0.12.0 failed during the configure step. The exception was: ExitFailure 1 so how can I get pkg-config on windows or how to install cairo then ? Do you have the cairo development files installed? Recall this isn't the same as having a cairo dll! See the Windows section of their download page for binaries . Also, you can run cabal install -v for more verbosity in the error (which you should post if you're still stuck). you need

Setup: I have a Haskell library HLib which makes calls to a C/C++ backend CLib for efficiency. The backend is small and specialized for use with HLib . The interface to CLib will only be exposed through HLib ; HLib tests, HLib benchmarks and third party libraries depending on HLib will not make direct FFI calls to CLib . From the test/benchmark/3rd party lib perspective, HLib should be appear purely Haskell. This means in the cabal file sections for, e.g., HLib tests, there should be no references to -lCLib , libCLib , etc, only a build-depends on HLib , and that executables should not need to