Tools to support multiple GHC distributions in a Bash shell environment
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.

Managing Multiple GHC Distributions

The multi-ghc repository contains tools for managing multiple distributions of GHC in a single system. It simplifies the installation process and switching the current environment to use one GHC+Cabal.

What's Inside

  • ghc-config - A Bash script that sets up the environment and switches between GHC+Cabal paths. This works primarily using directory conventions and symbolic links.

  • Makefile - For symplifying the building of Linux binary tarballs.

How to Use

  1. Create a directory for your GHC distributions. We'll call this directory $GHC_DISTRIBUTION_DIR for now.

  2. Clone this repository into $GHC_DISTRIBUTION_DIR.

  3. Add the following to your startup scripts (i.e. your .bashrc or .bash_profile):

    # These environment variables are only necessary if you don't use the defaults
    # shown.
    # Add the paths for ghc-config, ghc, and cabal-installed binaries. Use
    # the actual paths if you don't set the variables above.
    PATH=$PATH:$GHC_DISTRIBUTION_DIR/bin  # ghc-config
    PATH=$PATH:$GHC_CONFIG_DIR/ghc/bin    # ghc
    PATH=$PATH:$CABAL_USER_DIR/bin        # cabal and cabal-installed binaries
    # Initialize the current configuration for this session.
    ghc-config -i
  4. Install a GHC distribution into sudirectories of $GHC_DISTRIBUTION_DIR/$GHC_VERSION/src, where $GHC_VERSION is that particular GHC version number. For example:

    $ ls /opt/ghc/6.10.4/src
    ghc-6.10.4/  ghc-6.10.4-i386-unknown-linux-n.tar.bz2
  5. Create a symbolic link to the included Makefile in $GHC_DISTRIBUTION_DIR.

    $ cd /opt/ghc/6.10.4
    $ ln -s ../Makefile
  6. Install the $GHC_VERSION of GHC using the Makefile. This will use the directory and naming conventions established by the previous steps. See the `Makefile for details.

    $ make install
  7. Restart your shell.

  8. Run ghc-config to see the help information.

  9. Run ghc --version to confirm that GHC works.

  10. Install cabal by downloading the latest tarball and running the script.

  11. Run cabal --version to confirm that cabal-install works.

Questions or Contributions

I welcome feedback (constructive criticism, suggestions, etc.). Send me a message on GitHub, or email me.

Sean Leather