[racket-dev] syntax-local-inferred-name, keyword functions, and syntax properties

From: Sam Tobin-Hochstadt (samth at cs.indiana.edu)
Date: Mon Dec 9 16:29:42 EST 2013

I haven't found a way to make it happen yet.  But even so, it seems
like the wrong name.


On Mon, Dec 9, 2013 at 4:16 PM, Robby Findler
<robby at eecs.northwestern.edu> wrote:
> Is it possible that that name can leak out in an error message?
> Robby
> On Mon, Dec 9, 2013 at 3:10 PM, Sam Tobin-Hochstadt <samth at cs.indiana.edu>
> wrote:
>> Currently, this program fails with a somewhat bizarre type error:
>>     #lang typed/racket
>>     (: foo ([#:k Any] -> Integer))
>>     (define (foo #:k [s #f]) 0)
>>     (let: ([i : Integer (foo #:k #t)]) i)
>> The reason is that the expansion of keyword applications generates a
>> name to use for the function (here `foo`), and it uses
>> `syntax-local-infer-name` to get the name to use. Unfortunately, in
>> this case, it produces `i`, an identifier which has an extra syntax
>> property saying that `i` is an `Integer`.  Of course, `foo` isn't an
>> integer, it's a function, and so we get a type error.
>> I don't see why the inferred name is the right choice here -- there's
>> no connection between `i` and the name of the function. I can just
>> change this to use a fresh name, but I thought I'd ask first.
>> Sam
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