is not longer used -> is no longer used
any arguments. It does not create a reference to the instance. The
cached method result will be kept only as long as the instance is alive.
-The advantage is that when an instance is not longer used, the cached
+The advantage is that when an instance is no longer used, the cached
method result will be released right away. The disadvantage is that if
instances accumulate, so too will the accumulated method results. They
can grow without bound.