keywords='if then else elif fi while until for do done { } case esac ! in'

# Keywords can be used unquoted in case statements, except the keyword
# esac as the first pattern of a '|' alternation without a starting '('.
# (POSIX doesn't seem to require (esac) to work.)
for k in $keywords; do
	eval "case $k in (foo|$k) ;; *) echo bad ;; esac"
	eval "case $k in ($k) ;; *) echo bad ;; esac"
	eval "case $k in foo|$k) ;; *) echo bad ;; esac"
	[ "$k" = esac ] && continue
	eval "case $k in $k) ;; *) echo bad ;; esac"
done