[racket-dev] syntax-case and stack trace

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Sat Jul 16 10:30:26 EDT 2011

On Jul 16, 2011, at 8:19 AM, Matthew Flatt wrote:

> At Fri, 15 Jul 2011 21:53:59 -0500, Casey Klein wrote:
>> FWIW, the big taints commit also changed the value of this expression:
>> 
>> (let ([s #'x])
>>  (equal? s
>>          (with-handlers ([exn:fail:syntax? (compose first
>> exn:fail:syntax-exprs)])
>>            (raise-syntax-error #f "message" s))))
> 
> That's intentional, although I don't think it's correctly documented
> (and probably not yet implemented right) that syntax objects in an
> `exn:fail:syntax' are always tainted. I'll work on that.
> 
> The expression could be fixed for taints as
> 
>  (let ([s (syntax-taint #'x)])
>    (equal? s
>            ....))

Will taint information show up in the syntax objects in the drr repl? 


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