#1794: (r7rs) syntax-rules doesn't allow combining ellipsis and dotted tail

[Chicken Trac]

#1794: (r7rs) syntax-rules doesn't allow combining ellipsis and dotted tail
--------------------------------+----------------------------------------
            Reporter:  sjamaan  |       Type:  defect
              Status:  new      |   Priority:  major
           Milestone:  5.4      |  Component:  unknown
             Version:  5.3.0    |   Keywords:  r7rs, syntax-rules, macros
Estimated difficulty:  medium   |
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 According to the R7RS spec, the following should match:

 {{{
 (define-syntax match-ellipsis-and-dotted-tail1
   (syntax-rules ()
     ((_ a ... . b)
      '(a ... b))))

 (print (match-ellipsis-and-dotted-tail1 x y . z))
 }}}

 And this, too:

 {{{
 (define-syntax match-ellipsis-and-dotted-tail2
   (syntax-rules ()
     ((_ (a) ... . (b))
      '(a ... b))))

 (print (match-ellipsis-and-dotted-tail2 (x) (y) z))
 }}}

 Both should print `(x y z)`.

 Might be nice to support this in the core `syntax-rules`, or if it's too
 tricky, we could just support it only in the R7RS egg.

-- 
Ticket URL: <https://bugs.call-cc.org/ticket/1794>
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