support for (... ...) ellipsis quoting? (Was: local syntax-rules)

[Lars J. Aas]

On Tue, Nov 07, 2000 at 12:23:28PM +0200, Ivan Toshkov wrote:
: Lars J. Aas writes:
:  > On Mon, Nov 06, 2000 at 05:14:08PM +0100, Lars J. Aas wrote:
:  > :   (define-syntax argtypes
:  > :     (let-syntax ((argtype (syntax-rules ()
:  > :                             ((argtype (name type)) type)
:  > :                             ((argtype name) <top>))))
:  > :       (syntax-rules ()
:  > :         ((argtypes arg) (cons (argtype arg) '()))
:  > :         ((argtypes arg arg1 ...) (cons (argtype arg) (argtypes arg1 
...))))))
:  > : 
:  > : Should I use let-syntax in another way (e.g. *inside* the argtypes 
syntax-rules)?
: 
: If I think of something I'll let you know :)  Meanwhile, why don't you try to
: post your question in comp.lang.scheme and see what they have to say about it?
: I guess most of the guile developers/users prefer lisp-style macros and that's
: why you don't get many answers here...

I did, and got this suggestion:

  (define-syntax argtypes
    (syntax-rules ()
      ((argtypes arg1 ...)
        (letrec-syntax ((argtype (syntax-rules ()
                                   ((argtype (name type)) type)
                                   ((argtype name) <top>)))
                        (argtypes (syntax-rules ()
                                    ((argtypes arg)
                                      (cons (argtype arg) '()))
                                    ((argtypes arg arg1 (... ...))
                                      (cons (argtype arg)
                                            (argtypes arg1 (... ...)))))))
          (argtypes arg1 ...)))))

The (... ...) construct is a non-R5RS extension for quoting ellipsis, which
supposedly was supported by most R5RS scheme implementations, but it doesn't
seem to be supported in Guile because I get this error:

ERROR: missing ellipsis in syntax form (syntax (letrec-syntax ((argtype [...]
ABORT: (misc-error)

Can anyone confirm that the (... ...) convention is unsupported?

I'm going to try to rewrite it using the single-dot pattern notation instead
(which is R5RS) to see if I can get that to work...

  Lars J