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Anyway, I disagree. I don't think there's a use case for DoubleEndedIterator at the moment -- none of the current users of clist need reverse iteration. I'd prefer to keep the interface minimal and add it when there's an actual need for it, rather than adding API surface that nobody uses. If a usecase comes up, we can always trivially add it. (will look at other comments in the morning, its night for me). Thanks, -- Joel Fernandes