[plt-dev] syntax-case error messages
On Mar 30, 2010, at 7:45 AM, Ryan Culpepper wrote:
> Really? I read the first as the macro saying "No, you got it wrong.
> Read the docs/source and figure it out." Not the most helpful error
> message, maybe, but since macro interfaces are so much more free-
> form than procedure interfaces, it's harder to say exactly what went
> wrong.
>
> The other error message, on the other hand, has very much an
> internal error feel to it.
Thank you for boiling it all down to such a short summary. Syntax --
like it or not -- has a radically different status than values. Most
programmers who approach Racket will NOT have programmed in a world
where syntax is just another library 'thing'. Instead they come from a
world where parsing signals mistakes and when something from the
inside of the parser spills out, it's a compiler bug.
[Of course, it is a compiler bug for us, too, because macros are a
compiler API. But we don't have to be blatant about it.]
-- Matthias