[racket] help about a macro that uses a struct define with "make-struct-type"

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Fri Jul 29 11:11:24 EDT 2011

On Jul 29, 2011, at 10:57 AM, Maurizio Giordano wrote:

>> Your question isn't clear. 
> You are right! I try to clarify my point...
> The problem is in the "(map (lambda ... l2)" expression, not in the
> syntax the macro produces. 
> It is ok when I reference "l1" in the line:
> "(datum->syntax stx `(map (lambda (x) (print-type x)) ,l1)"
> In fact, the struct "<...>" is recognized correctly in l1 as a "mset"
> type. 
> It is not in the "(map (lambda ... l2)". For some reason (I bet you
> know) the same struct "<...>" IS NOT recognized as a "mset" in the map.
> I suppose the input list (l2), when parsed, is stripped out of some
> information about user defined (not-prefab) struct. But more likely I am
> simply using the macro in a wrong way. 

Then why don't you may over l1? -- Matthias (still confused)

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