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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/>.
#
# This isn't perfect behavior, but it establishes a baseline and will provide
# a way to detect behavior changes
echo a1
a[0]= a[1]=; recho "${a[@]:-y}"
unset a
echo a2
a[1]=; recho "${a[@]:-y}"
a[1]=; recho "${a[*]:-z}"
unset a
echo a3
a[0]= a[1]=x; recho "${a[@]:-y}"
unset a
echo a4
a[0]= a[1]=x; recho ${a[@]:+y}
unset a
echo p1
set '' ''
recho "${@:-y}"
shift $#
echo p2
set '' x
recho "${@:-y}"
shift $#
echo p3
set '' x
recho ${@:+y}
# problems with * and null expansions dating back to bash's earliest days
A=(''); set -- ''
echo "<${A[*]:-X}>" "<${*:-X}>" "<${A:-X}>" "<${A[0]:-X}>"
IFS=
A=('' ''); set -- '' ''
B=''
echo "<${A[*]:-X}>" "<${*:-X}>" "<${B:-X}>" "<${B[*]:-X}>"
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