We now warn on the ambiguity of >> or ยป when used where it could easily be intended as either a hyper or the quotewords terminator. While we could, in theory, do some lookahead to try to suppress this warning in some cases, it will be brittle in the face of languages that mutate the postfix space, so I think it's better to just warn outright and let people disambiguate with whitespace or a suitable change to the hyper or quote delims.
(As for retargeting this ticket to the more general case of multiline quote errors, please note that a runaway hyper is not a kind of quote, and that we already warning on runaway quotes that cross line boundaries. Also, the problem here is essentially independent of multi-line-ness. So I've changed the title of this bug back to the original, since that's the problem we're fixing.)
