#   This program is free software: you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# nameref requires changes to unset
bar=one
typeset -n foo=bar

# normal unset unsets only variable nameref references
# need unset -n to unset nameref itself
unset foo
echo "expect <unset>"
recho ${bar-unset}
echo "expect <unset>"
recho ${foo-unset}
echo "expect <bar>"
recho ${!foo}
unset -n foo
echo "expect <unset>"
recho "${!foo-unset}"

readonly bar=two
typeset -n foo=bar

unset foo	# this should fail because bar is readonly

echo "expect <two>"
echo ${bar-unset}
echo "expect <two>"
echo ${foo-unset}

# one question is what happens when you unset the underlying variable
qux=three
typeset -n ref
ref=qux

echo $ref
unset qux
echo ${ref-unset}
qux=four
echo ${ref-unset}