[r6rs-discuss] macroexpand

From: Sam TH <samth>
Date: Fri Sep 22 16:40:28 2006

On Fri, 2006-09-22 at 23:06 +0300, Dan Muresan wrote:

> You do realize, of course, that I'm already doing things with define-macro
> /macroexpand that cannot be done without them? And you're saying the
> language should protect me from myself and the things I have accomplished?
> Thanks, but no thanks.

I spend lots of time using `local-expand' in PLT Scheme, which is an
invaluable tool for some macros. Further, it works correctly for
hygenic macros, which `expand' does not. So I understand why someone
would want this feature.

However, it's a complicated extension to the macro system, which would
require careful specification (it's not just exposing the expander).
Therefore, it's appropriate not to specify it right now - there's only
so much that can be done in one revision.

Similarly, an FFI is very important for a programming language, but R6RS
isn't going to specify one. That isn't a sign the R6RS process is
failing, or that we should adopt a half-baked solution so that we can
specify something now.

sam th
Received on Fri Sep 22 2006 - 16:41:02 UTC