~ubuntu-branches/ubuntu/trusty/bash/trusty-security

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# 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"