[plt-scheme] paren-shape bug?

From: Dimitris Vyzovitis (vyzo at media.mit.edu)
Date: Tue Apr 28 19:48:38 EDT 2009

On Tue, 28 Apr 2009, Ryan Culpepper wrote:

> I'm surprised that it still loses properties. Exactly how  are you doing 
> it?

I tried this a while ago -- I made syntax/quasisyntax replacement wrappers 
that worked together with a custom syntax-rules variant.
It wasn't pretty, and I am not sure I want to dig for this code.
It is also likely that I did something subtly wrong, but the code was so 
unsatisfactory that I junked it almost immediately when I realized it still
didn't work.

> It could also be fixed at the level of 'syntax-case', 'syntax' etc. They 
> could store the shape separately from the pattern. You could generalize that 
> to storing other properties, too. The code is in scheme/private/stxclass and 
> scheme/private/sc, though; I don't see a good way to change or reuse it from 
> outside.

I think fixing it inside would the right way to do it.
I have implemented the reader macro for now, it works until 
you throw a []/{} to an unsuspecting macro in non-expression position.
(let's see how long before I junk this one :)

-- vyzo

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