On Thu 12 May 2011 14:36, Jim Rees <[email protected]> writes: > On Thu, May 12, 2011 at 7:36 AM, Alaric Snell-Pym <[email protected]> > 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/ _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
