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Re: [Scheme-reports] [wg2] in support of single-arity procedural syntax transformers



On Thu 12 May 2011 14:36, Jim Rees <jimreesma@x> writes:

> On Thu, May 12, 2011 at 7:36 AM, Alaric Snell-Pym <alaric@x> wrote:
>
>     But what happens if you try to REVERSE a syntax-object wrapping a list?
>     You can't - 
>
> Overall your essay is illuminating, but reversing a syntax-object
> representing a list is easy in an R6RS-conforming implementation.
>
> (define (reverse-wrapped-list obj)
>   (syntax-case obj ()
>     ((e ...) (reverse #'(e ...)))))

This works on psyntax systems, where lists are never wrapped, but AFAIK
it does not work on Racket, where lists are wrapped.

Andy
-- 
http://wingolog.org/

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