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Re: [Scheme-reports] Legacy caar to cddddr



On Sat, 22 Oct 2011, John Cowan wrote:

> Andre van Tonder scripsit:
>
>>      (define-syntax do
>>       (er-transformer
>>        (lambda (exp r c)
>>          (or (and (pair? (cdr exp))
>>                   (pair? (cddr exp)))
>>              (syntax-error))
>>          (let ((specs (cadr exp))
>>                (end (caddr exp))
>>                (body (cdddr exp))
>>                (loop (syntax loop)))
>
> It's not obvious why this is better than pattern-matching, though.

I thought WG2 had made a preliminary decision to have renaming macros
(i.e., no syntax-case).


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