An expert writes,

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You might want to consider adding something like the following to the
asLifoQueue(Deque) javadoc (modified from newSetFromMap):

"Each method invocation on the queue returned by this method results in
exactly one method invocation on the backing deque, with one exception. The
addAll method is implemented as a sequence of addFirst invocations on the
backing deque."

The newSetFromMap specifies this detail so it might be useful if the
asLifoQueue did too.
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