Thanks!

On Wed, May 27, 2009 at 1:44 PM, lowly coder <lowlycoder@huoyanjinjing.com> wrote:

Cool, thanks!

Another quesiton on define-type -- is there anyway to get back an unique identifier for the type?

i.e. if I have:

(define f1 (make-foo ..))

(define f2 (make-foo ...))

(define b1 (make-bar ..)))

I want something so that

(equal? (type f1) (type f2)) and
(not (equal? (type f1) (type b1)))

the idea is then, I can do dispatching on types i.e.

(define (draw object)
((lookup-in-hash-table (type object)) object))

Thanks!

On Wed, May 27, 2009 at 5:14 AM, David St-Hilaire <sthilaid@iro.umontreal.ca> wrote:

lowly coder wrote:

Hey,

Where is define-type documented? I can't find it in r5rs or in the gambit documentation (though it is briefly mentioned in a tour of scheme through gambit). define-type is really cool and I'm starting to run against my limited knowledge of it.

Hi there!

I've put some of Marc's undergrad notes related to define-type in the gambit-c wiki a while ago:

http://dynamo.iro.umontreal.ca/~gambit/wiki/index.php/Define-type

Hope it can help!

David