[racket] variables within macros

Danny, Jens Axel, Ian, Ray,

Thanks for your input... I'm absorbing it all.

I need some really basic help getting my head around all of this.
Where can I download a copy of "How to Design Macros"? :-)

Tim

On 16/01/13 17:22, Jens Axel Søgaard wrote:
> Hi Tim,
>
> Danny explains the problem well.
> To accumulate a result, one must stay in the same
> same dynamic extent. One way to solve the problem
> is to use local-expand. In some cases one can
> write expanders  for the forms, that needs analysing
> and call them directlye (rather than write a macro
> for the subform and then let the expander
> call a macro transformer).
>
> Below is a short example, which incidently shows
> an alternative solution the local-expand problem,
> I had the other day
> (see  http://www.mail-archive.com/users@racket-lang.org/msg15937.html ).
>
> If you need local-expand, then see Matthews answer on how
> to use definition contexts with local-expand.
>
> /Jens Axel

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