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# nameref requires changes to unset
bar=one
typeset -n foo=bar
# normal unset unsets only variable nameref references
# need unset -n to unset nameref itself
unset foo
echo "expect <unset>"
recho ${bar-unset}
echo "expect <unset>"
recho ${foo-unset}
echo "expect <bar>"
recho ${!foo}
unset -n foo
echo "expect <unset>"
recho "${!foo-unset}"
readonly bar=two
typeset -n foo=bar
unset foo # this should fail because bar is readonly
echo "expect <two>"
echo ${bar-unset}
echo "expect <two>"
echo ${foo-unset}
# one question is what happens when you unset the underlying variable
qux=three
typeset -n ref
ref=qux
echo $ref
unset qux
echo ${ref-unset}
qux=four
echo ${ref-unset}
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