[plt-dev] syntax-case error messages

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Tue Mar 30 09:12:11 EDT 2010

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

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