[plt-scheme] Problem with syntax-case macro under MzScheme 352

From: Sam Tobin-Hochstadt (samth at ccs.neu.edu)
Date: Sat Sep 9 13:42:49 EDT 2006

On Sat, 2006-09-09 at 10:59 -0400, Shriram Krishnamurthi wrote:
> So the problem was simply that a constructed value was
> being injected back into syntax land without being properly
> type-coerced.  That's something a syntax "type" system ought
> to be able to catch.

`with-syntax' applies an implicit type coercion, so the original code is
really like 

(with-syntax ([name (datum->syntax-object #f --rest--)])
   --body--)

Maybe this is a bad idea (although I find it very convenient), but I
don't think a type system (at least one that ran after expansion) would
catch this error.

sam th



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