source this file; cd to apertium language pair / language dir by saying "ca some pair" or "ca somelang"

apertium-ca.sh

#!/bin/bash

# Save this file to e.g. ~/src/apertium-ca.sh, then put "source
# ~/src/apertium-ca.sh" in ~/.bashrc Now you can type "ca nno" to go
# to languages/apertium-nno and "ca kir kaz" to go to
# nursery/apertium-kaz-kir – even though it's in the other order

export APERTIUM_SVNROOT=$HOME/src/apertium

ca () {
    declare -a modes dirs
    declare -A pairsdirs langsdirs

    modes=( "${APERTIUM_SVNROOT}"/{trunk,incubator,nursery,staging,languages}/apertium-*/modes.xml )
    dirs=( ${modes[@]%/modes.xml} )

    add_langsdir () {
	if [[ ${langsdirs[$1]+isset} ]]; then
	    langsdirs[$1]="$2\n${langsdirs[$1]}"
	else
	    langsdirs[$1]=$2
	fi
    }

    for dir in "${dirs[@]}"; do
	pair=${dir##*apertium-}
	if [[ ${pair} = *-* ]]; then
	    from=${pair%%-*}
	    to=${pair##*-}
	    pairsdirs[${from}-${to}]=${dir}
	    pairsdirs[${to}-${from}]=${dir}
	    add_langsdir ${from} ${dir}
	    add_langsdir ${to} ${dir}

	    # interpret nor as both nob and nno:
	    if [[ ${from} = nor ]]; then
		pairsdirs[nno-${to}]=${dir}
		add_langsdir nno ${dir}
		pairsdirs[nob-${to}]=${dir}
		add_langsdir nob ${dir}
	    elif [[ ${to} = nor ]]; then
		pairsdirs[${from}-nno]=${dir}
		add_langsdir nno ${dir}
		pairsdirs[${from}-nob]=${dir}
		add_langsdir nob ${dir}
	    fi
	else
	    pairsdirs[${pair}]=$dir
	    add_langsdir ${pair} ${dir}
	fi
    done

    case $# in
	1) cd "${pairsdirs[$1]}";;
	2)
	    if [[ $1 = -l ]]; then
		if [[ ${langsdirs[$2]+isset} ]]; then
		    echo -e "${langsdirs[$2]}"
		else
		    echo "No directories found for language code $2"
		    return 1
		fi
	    else
		cd "${pairsdirs[$1-$2]}"
	    fi
	    ;;
	*)
	    echo "Usage: "
	    echo "$0 nob nno    cd to the directory containing a pair of nob and nno (even though it's named apertium-nno-nob)"
	    echo "$0 nno        cd to the directory containing apertium-nno"
	    echo "$0 -l nno     list all apertium directories with nno in the name"
	    return 2
	    ;;
    esac
    return 0
}