[plt-scheme] define-syntax help

From: support at taxupdate.com (support at taxupdate.com)
Date: Fri Mar 23 07:40:42 EDT 2007


On Fri, Mar 23, 2007 at 09:07:52AM -0700, Noel Welsh wrote:
> I see.  I think you can achieve your goals in other ways -- and this is the approach
> I would use as I think the semantics are easier to understand and implement.
> Specifically, you can create a new scheme-like language that, for example, quotes
> any undefined symbol.  More specifically, you want to change how #%top (or
> #%top-interaction) works.
>   http://docs.plt-scheme.org/mzscheme/mzscheme-Z-H-12.html#node_idx_3092
> This stuff is really powerful and easier to implement than macros (IMO).

Looks interesting.  The docs don't really give much guidance on changing #%top,
though.  Is it a matter of doing something like (define-syntax (#%top stx) ...) ?
> Your other problem, the implicit context of lookup, you can solve using a parameter.

I started to look at the docs on this, and it seems I'd have to convert any
syntax which uses this to functions, right?  Unless the parameterization would
be available during syntax expansion?


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