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

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Mon Dec 9 16:35:26 EST 2013

Oh, now I get what you meant in your original message. Right.

Robby


On Mon, Dec 9, 2013 at 3:29 PM, Sam Tobin-Hochstadt <samth at cs.indiana.edu>wrote:

> I haven't found a way to make it happen yet.  But even so, it seems
> like the wrong name.
>
> Sam
>
> 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
> >> _________________________
> >>   Racket Developers list:
> >>   http://lists.racket-lang.org/dev
> >
> >
>
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