#!/bin/bash
[ -z "$1" ] && echo "usage: $0 <cmd> [<arg> ...]" && exit 1

diff_git() {
    git diff
}
diff_darcs() {
    darcs whatsnew
}

commit_git() {
    git commit -am "$1"
}
commit_darcs() {
    darcs rec -am "$1"
}

add_darcs() {
    darcs add $1
}
add_git() {
    git add $1
}


if (git status >/dev/null 2>/dev/null); then
    CMD="$1_git"
else
    CMD="$1_darcs"
fi
shift
$CMD "$@"