build-lens

#!/bin/bash
set -e
# set -x

help_text() {
    echo "Usage:
  ${0##*/} [-h] cabal [-- cabal opts]

Options:

  -h, --help
    display this help and exit"
}

CABAL=
while [ "$#" -gt 0 ]; do
    case "$1" in
        -h|--help) help_text; exit;;
        --) shift 1; break;;
        -*) echo "unknown option: $1" >&2; exit 1;;
        *) if [ -z $CABAL ]
           then CABAL="$1"
           else args+="$1"
           fi
           shift 1;;
    esac
done

if [ -z $CABAL ]; then
    echo "No cabal selected" >&2
    exit 1
fi

custom_pkgs="distributive comonad semigroupoids lens-head"

for pkg in $custom_pkgs; do
    echo "Building $pkg"
    CABAL_FLAGS=
    case $pkg in
        *-head) CABAL_FLAGS+=" --source-repository=head"; pkg="${pkg%-*}";;
        *) pkg=$pkg
    esac
    # use system cabal to get the package, until we are certain that $CABAL
    # supports get properly.
    cabal get $pkg $CABAL_FLAGS || true
    cd $pkg*
    # replace the custom build type with the simple build type.
    # this is UNSAFE! an not necessarily guaranteed to work!
    sed -i.bak -E 's/(build-type:[ ]+)Custom/\1Simple/g' *.cabal
    $CABAL install "$@"
    cd ..
done