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# Copyright 2025 The Free Software Foundation
#
# 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/>.
#
# let's see how various arithmetic contexts handle embedded double quotes and
# empty expressions
declare -a a
afunc()
{
a[0]=0
( a[" "]=10 ; declare -p a )
( (( a[" "]=11 )) ; declare -p a )
( : $(( a[" "]=12 )) ; declare -p a )
( let a\[" "\]=13 ; declare -p a )
( declare "a[\" \"]=14" ; declare -p a )
( a[\" \"]=15; declare -p a )
( (( a[\" \"]=16 )) ; declare -p a )
( : $(( a[\" \"]=17 )) ; declare -p a )
( let "a[\" \"]"=18 ; declare -p a )
( a[\"\"]=19 ; declare -p a )
( (( a[\"\"]=20 )) ; declare -p a )
( : $(( a[\"\"]=21 )) ; declare -p a )
( let "a[\"\"]"=22 ; declare -p a )
( a[""]=23 ; declare -p a )
( (( a[""]=24 )); declare -p a )
( : $(( a[""]=25 )); declare -p a )
( let 'a[""]=26' ; declare -p a )
}
echo == arraysub ==
shopt -u assoc_expand_once
echo === assoc_expand_once unset ===
afunc
unset a
declare -a a
shopt -s assoc_expand_once
echo === assoc_expand_once set ===
afunc
unset a
echo == substring ==
a=12345
echo ${a:0:2}
echo ${a::2}
echo ${a:2:0}
echo ${a:2:}
echo ${a:2}
echo == cond ==
[[ "" -gt 1 ]] ; echo $?
[[ 1 -le "" ]] ; echo $?
[[ 0 -eq "" ]] ; echo $?
echo == arithsub ==
echo $(( )) ; echo 1 $?
echo $(( "" )) ; echo 2 $?
echo $(( \"\" )) ; echo 3 $?
echo $(()) ; echo 4 $?
a=$(( )) ; echo 5 $?
a=$(( "" )) ; echo 6 $?
echo == arithcmd ==
(( )) ; echo 1 $?
(( "" )) ; echo 2 $?
(( " " )) ; echo 3 $?
(( 1 - "" )) ; echo 4 $?
echo == letbltin ==
let '' ; echo 1 $?
let ' ' ; echo 2 $?
let '0 - ""' ; echo 3 $?
let "0 - \"\"" ; echo 4 $?
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