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On Fri, 10 Oct 2003, Taylor Campbell wrote: >Since with this SRFI it becomes possible to put literal ellipsis in the >_template_, it seems like it would be useful to also be able to match >literal ellipsis in the _pattern_, while still being able to use >ellipsis >to match multiple inputs. However, I cannot think of a nice and concise >way to do this: enabling literal ellipsis to be present in the literal >identifier list would prohibit the macro from using ellipsis to match >multiple inputs. Any comments on this idea, and how to go about it? It would certainly be possible to do it using an additional identifier; An "obvious" choice, which is a legal identifier according to R5RS, would be ::: . Other "obvious" choices which are legal identifiers include <...> or /.../ . The first of those two is particularly tasty because it allows a general "nested" syntax; you could use <<...>>, <<<...>>>, etc, for more layers of nesting. One thing to remember though, is that an ellipsis matches anything in the code it's matching against -- including another ellipsis. So there may actually be no issue here. Bear