“Memoized construction” is a very good name, indeed. It's actually better than “hash consing”, because it isn't tied to a particular implementation strategy. Bu

“Memoized construction” is a very good name, indeed. It's actually better than “hash consing”, because it isn't tied to a particular implementation strategy. But I think the “handrolled” part is also important, to stress that it isn't something the language implementation gives you for free.