[plt-scheme] macro type

--- Ivanyi Peter <pivanyi at freemail.hu> wrote:

> instead I would like to have somthing like this:
> 
> > cond
> #<macro:cond>

This doesn't make sense in PLT Scheme's model -- macros
exist at expansion time, not runtime.  I suppose it could
be possible in a system that interleaves expansion and
runtime (I imagine older implementations did this) but the
module system is designed to avoid this -- and this is a
good thing.

> and in this case I also would like to have
> 
> > (macro? cond)
> #t


It is possible this could be implemented as a macro. 
Macros can query the binding of identifiers (see
http://download.plt-scheme.org/doc/350/html/mzscheme/mzscheme-Z-H-12.html#node_sec_12.3.2)
 I don't know if or how this can be extended to macros, but
it might be possible.

N.

Email: noelwelsh <at> yahoo <dot> com   noel <at> untyped <dot> com
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