Install Haskell from Scratch

haskell-mtn-lion.sh

#!/bin/bash -eux

ARCH=${ARCH:-x86_64}
CORES=$(sysctl -n hw.ncpu)
GHC=${GHC:-7.4.2}
CABAL=${CABAL:-0.14.0}
PLATFORM=${PLATFORM:-2012.2.0.0}

[[ ! -d /usr/local/src ]] && mkdir -p /usr/local/src

cd /tmp
[[ ! -f ghc-${GHC}-${ARCH}-apple-darwin.tar.bz2 ]] && \
    curl -O http://www.haskell.org/ghc/dist/${GHC}/ghc-${GHC}-${ARCH}-apple-darwin.tar.bz2
[[ ! -d ghc-${GHC} ]] && \
    tar xf ghc-${GHC}-${ARCH}-apple-darwin.tar.bz2
cd ghc-${GHC}
./configure --prefix=/tmp
make install
export PATH=/tmp/bin:$PATH

cd /tmp
[[ ! -f cabal-install-${CABAL}.tar.gz ]] && \
    curl -O http://hackage.haskell.org/packages/archive/cabal-install/${CABAL}/cabal-install-${CABAL}.tar.gz
[[ ! -d cabal-install-${CABAL} ]] && \
    tar xf cabal-install-${CABAL}.tar.gz
cd cabal-install-${CABAL}
rm -rf ~/.cabal ~/.ghc
PREFIX=/tmp bash ./bootstrap.sh --global
cabal update
cabal install --global --prefix=/tmp happy
cabal install --global --prefix=/tmp alex

cd /usr/local/src
[[ ! -f ghc-${GHC}-src.tar.bz2 ]] && \
    curl -O http://www.haskell.org/ghc/dist/${GHC}/ghc-${GHC}-src.tar.bz2
[[ ! -d ghc-${GHC} ]] && tar xf ghc-${GHC}-src.tar.bz2
cd ghc-${GHC}
# http://hackage.haskell.org/trac/ghc/ticket/7040 x86_64 problem
curl http://hackage.haskell.org/trac/ghc/raw-attachment/ticket/7040/ghc7040.patch | patch -p1
./configure --build=${ARCH}-apple-darwin
make -j${CORES}
make install
export PATH=/usr/local/bin:$PATH

cd /usr/local/src
[[ ! -f haskell-platform-${PLATFORM}.tar.gz ]] && \
    curl -O http://lambda.haskell.org/platform/download/${PLATFORM}/haskell-platform-${PLATFORM}.tar.gz
[[ ! -d haskell-platform-${PLATFORM} ]] && \
    tar xf haskell-platform-${PLATFORM}.tar.gz
cd haskell-platform-${PLATFORM}
make clean
./configure --enable-unsupported-ghc-version
make -j${CORES}
make install