print_versions

#! /bin/sh

get_erl_version()
{
    which erl > /dev/null 2>&1
    if [ $? = 0 ]; then
        erl -noinput \
            -eval 'ok = io:put_chars(erlang:system_info(system_version))' \
            -s init stop
    else
        echo "NOT FOUND"
    fi
}

get_python_version()
{
    which python > /dev/null 2>&1
    if [ $? = 0 ]; then
        python --version 2>&1
    else
        echo "NOT FOUND"
    fi
}

get_ruby_version()
{
    which ruby > /dev/null 2>&1
    if [ $? = 0 ]; then
        ruby --version
    else
        echo "NOT FOUND"
    fi
}

display_versions()
{
    echo
    echo "====================== Versions ============================="
    echo "  Erlang: $(get_erl_version)"
    echo "  Python: $(get_python_version)"
    echo "  Ruby:   $(get_ruby_version)"
    echo "============================================================="
}

display_versions