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Re: Ellipses



David Feuer skrev:
I think Petrofsky's suggestion for handling ellipses (SRFI-46) is far
cleaner that the one in the SRFI-93 draft.  For syntax-rules macros, I
would recommend adopting the SRFI-46 method, or something very similar
to it.  As well as being easier to understand, I believe that the
current proposal would be expressible in Petrofsky's syntax, but that
the converse does not hold.  For syntax-case macros, I think we should
take the opportunity to go all the way with Petrofsky's idea, and make
the ellipsis identifier a required argument to SYNTAX-CASE.

The only place (... ...) is needed is in macro-defining macros, which
aren't too common. A search through the PLT code base for (... ...)
versus a search for ... gives a good impression of how uncommon it is.
In my opinion it would therefore be annoying to the specify the ellipsis
in the "boiler plate" every time I need to define a standard macro.

Furthermore with-syntax lets you choose your own ellipsis, when
you need to define a macro-defining macro:

  (with-syntax ((::: #'(... ...))
    <use ::: here>)

--
Jens Axel Søgaard