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Re: Ellipsis in the _pattern_




On Sat, 11 Oct 2003, Taylor Campbell wrote:

>[ Slippinrippindangfangrottenzargbargadingdong!  I did it _again_! ]

>You've lost me here.  Ellipsis is for matching a sequence; how can
>ellipsis
>match literal ellipsis?  Are you talking about an arbitrarily nested
>number
>of ellipses, i.e. to be matched with (::: ...), in which case we _still_
>need :::?


You know, if it doesn't make sense to you it probably means the thing I'm
thinking about is a nonissue anyway.  As I said, I haven't eaten and breathed
enough macrology to fully understand the intent of ::: in the first place.
I just have the impression that if we actually need it, then something might
break down if we want to go to meta-macros or meta-meta macros and don't
have a corresponding "nested" form or the ability to produce/match it in
the inputs to our higher-order macros.

Still, the reason I doubt its actual utility is that I don't think anything
prevents ...  from matching a "sequence" of length one whose only member is
another ellipsis.

Maybe I should get embarassed about my ignorance here and shut up.

				Bear