[plt-scheme] Contract question

That function accepts a mandatory keyword parameter using the keyword
whose name just happens to be #:optional which, I'm guessing, is not
what you intended.

Anyways, here is its contract:

  (-> any/c #:optional any/c false/c)

If you wanted a function that takes either one or two arguments (as
the contract suggests), I think you meant to write it like this:

  (define (foo a [b #f]) #f)

(They keyword syntax changed a little bit from 372's (lib "kw.ss") to
4.0. Maybe that's the source of the confusion?)

Robby

On Fri, Jun 13, 2008 at 1:28 PM, David Einstein <deinst at gmail.com> wrote:
> How do I write a contract for the following
>
> (define (foo a #:optional b) #f)
>
> I would have thought that
>
> (provide/contract
>   [foo (->* (any/c) (any/c) false?)]
> )
>
> would work, but obviously I'm missing something.
>
>
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