#   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.
#
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#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# tests with blank subscripts, indexed and associative

echo 1. indexed:
a[0]=0 a[1]=1

v=" "

echo reference:

echo 1. ${a[ ]}
echo 2. ${a[' ']}
echo 3. "${a[ ]}"
echo 4. ${a[$v]}
echo 5. ${a["$v"]}
echo 6. "${a[$v]}"

echo assignment:

echo -n 1. ; a[ ]=10 ; typeset -p a ; a[0]=0
echo -n 2. ; a[" "]=11 ; typeset -p a ; a[0]=0
echo -n 3. ; a[$v]=12 ; typeset -p a ; a[0]=0
echo -n 4. ; a["$v"]=13 ; typeset -p a ; a[0]=0

echo arithmetic:

echo -n 1. ; (( a[ ]=10 )); typeset -p a ; a[0]=0
echo -n 2. ; (( a[" "]=11 )); typeset -p a ; a[0]=0
echo -n 3. ; (( a[$v]=12 )); typeset -p a ; a[0]=0
echo -n 4. ; (( a["$v"]=13 )); typeset -p a ; a[0]=0
echo -n 5. ; let "a[ ]=10" ; typeset -p a ; a[0]=0
echo -n 6. ; let "a[\" \"]=11" ; typeset -p a ; a[0]=0
echo -n 7. ; let "a[$v]=12" ; typeset -p a ; a[0]=0
echo -n 8. ; let "a[\"$v\"]=13" ; typeset -p a ; a[0]=0

unset -v a v

echo 2. associative:
shopt -s assoc_expand_once

typeset -A a
a[0]=0 a[1]=1

v=" "

echo reference:

echo 1. ${a[ ]}
echo 2. ${a[' ']}
echo 3. "${a[ ]}"
echo 4. ${a[$v]}
echo 5. ${a["$v"]}
echo 6. "${a[$v]}"

echo assignment:

echo -n 1. ; a[ ]=10 ; typeset -p a ; a[0]=0
echo -n 2. ; a[" "]=11 ; typeset -p a ; a[0]=0
echo -n 3. ; a[$v]=12 ; typeset -p a ; a[0]=0
echo -n 4. ; a["$v"]=13 ; typeset -p a ; a[0]=0

echo arithmetic:

echo -n 1. ; (( a[ ]=10 )); typeset -p a ; a[0]=0
echo -n 2. ; (( a[" "]=11 )); typeset -p a ; a[0]=0
echo -n 3. ; (( a[$v]=12 )); typeset -p a ; a[0]=0
echo -n 4. ; (( a["$v"]=13 )); typeset -p a ; a[0]=0
echo -n 5. ; let "a[ ]=10" ; typeset -p a ; a[0]=0
echo -n 6. ; let "a[\" \"]=11" ; typeset -p a ; a[0]=0
echo -n 7. ; let "a[$v]=12" ; typeset -p a ; a[0]=0
echo -n 8. ; let "a[\"$v\"]=13" ; typeset -p a ; a[0]=0