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

You're right. I misread the code. Yes, changing it seems good.

Robby


On Mon, Dec 9, 2013 at 3:56 PM, Sam Tobin-Hochstadt <samth at cs.indiana.edu>wrote:

> On Mon, Dec 9, 2013 at 4:50 PM, Robby Findler
> <robby at eecs.northwestern.edu> wrote:
> > I'm not really familiar with the way the keyword expansion works. I was
> just
> > trying to suggest "obvious" reasons why the code would do such a thing.
> >
> > But if you find that changing the name changes the error message, then
> > changing that would be bad.
>
> The point I'm trying to make is that I think the error message is
> _currently bad_, because there's no reason to think of that procedure
> as named `foo`. We'd be better off and less confused if the procedure
> in the error message didn't have a name.
>
> If you think changing it would be bad, why do you think the relevant
> procedure (the one with a keyword named `#:kk`) should be named `foo`?
>
> Sam
>
> >
> > Sorry for the noise.
> >
> > Robby
> >
> >
> > On Mon, Dec 9, 2013 at 3:41 PM, Sam Tobin-Hochstadt <
> samth at cs.indiana.edu>
> > wrote:
> >>
> >> Yes, that would work, but I still don't see why that's a useful name to
> >> use.
> >>
> >> Sam
> >>
> >> On Mon, Dec 9, 2013 at 4:37 PM, Robby Findler
> >> <robby at eecs.northwestern.edu> wrote:
> >> > Would it work to make it use syntax-local-infer-name but only use the
> >> > symbolic part of that name?
> >> >
> >> > Robby
> >> >
> >> >
> >> >
> >> > On Mon, Dec 9, 2013 at 3:34 PM, Sam Tobin-Hochstadt
> >> > <samth at cs.indiana.edu>
> >> > wrote:
> >> >>
> >> >> Aha, I found the example:
> >> >>
> >> >>    (let ([foo ((lambda (#:kk x) (λ (x) x)) #:k 0)]) (foo 5))
> >> >>
> >> >> Has this error:
> >> >>
> >> >> application: procedure does not expect an argument with given keyword
> >> >>   procedure: foo
> >> >>   given keyword: #:k
> >> >>   arguments...:
> >> >>    #:k 0
> >> >>
> >> >>
> >> >> Note that if you make the keywords the same, `foo` is indeed bound to
> >> >> a procedure, but _not_ to the procedure referred to in the error
> >> >> message.
> >> >>
> >> >> Sam
> >> >>
> >> >> On Mon, Dec 9, 2013 at 4:29 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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