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# 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/>.
#
# can we unset the nameref attribute on variables with values that reference
# unset variables?
unset bar
declare -n foo="bar"
declare -p foo
declare +n foo
declare -p foo bar
declare -n foo
declare -p foo
# let's try removing the nameref attribute -- other attributes and assignments
# apply to the nameref target
declare +n -i foo=7+4
declare -p foo bar
unset foo bar
# but if the nameref variable doesn't have a value, the attributes apply to
# the nameref variable itself. thanks ksh93
declare -n foo6
declare -xi foo6
declare -p foo6
# and when we remove the nameref attribute, the other attributes remain
declare +n foo6
declare -p foo6
unset foo6
# make sure these cases continue to work
# nameref referencing an existing, set variable
declare -n foo=bar
bar='Hello World!'
declare -p foo bar
declare +n foo
declare -p foo bar
unset foo bar
# nameref referencing an existing, unset variable
declare -n foo=bar
declare bar
declare -p foo bar
declare +n foo
declare -p foo bar
# but when we add the nameref attribute, we remove other attributes
declare -i ivar
ivar=4+4
echo $ivar
declare -n ivar=foo
declare -p ivar
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