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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/>.
#
# nameref variables as for loop index variables are special
v1=1
v2=2
# simple for loop
for v in v1 v2
do
typeset -n ref=$v
echo $ref
done
unset v
set -- first second third fourth fifth
# unless you put a ${!v} in the for loop, ksh93 misbehaves
typeset -n v=v1
for v in v1 v2; do
echo "${!v}: $v"
done
unset v
# example cribbed from ksh93 o'reilly book
first="I am first"
second="I am in the middle"
third="I am last"
typeset -n ref=first
for ref in first second third ; do
echo "ref -> ${!ref}, value: $ref"
done
echo final state: "ref -> ${!ref}, value: $ref"
readonly one=1
readonly two=2
readonly three=3
typeset -n ref=one
for ref in one two three; do
echo "ref -> ${!ref}, value: $ref"
done
echo final state: "ref -> ${!ref}, value: $ref"
unset ref
typeset -n ref=one
readonly ref
for ref in one two three; do
echo "ref -> ${!ref}, value: $ref"
done
echo final state: "ref -> ${!ref}, value: $ref"
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