dnl ../doc/m4.texinfo:1447: Origin of test
define(`reverse', `ifelse($#, 0, , $#, 1, ``$1'',
			  `reverse(shift($@)), `$1'')')
dnl @result{}
reverse
dnl @result{}
reverse(foo)
dnl @result{}foo
reverse(foo, bar, gnats, and gnus)
dnl @result{}and gnus, gnats, bar, foo