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.

--
John Cowan    http://ccil.org/~cowan    cowan@ccil.org
[T]here is a Darwinian explanation for the refusal to accept Darwin.
Given the very pessimistic conclusions about moral purpose to which his
theory drives us, and given the importance of a sense of moral purpose
in helping us cope with life, a refusal to believe Darwin's theory may
have important survival value. --Ian Johnston

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