On Apr 27, 2012, at 5:55 PM, Asumu Takikawa wrote: > You can write that, but the following isn't very useful: > (and/c (class/c #:opaque [m (->m number? number?)]) > (class/c #:opaque [n (->m number? number?)])) > > Since the two class contracts both reject classes that the other would > accept (unless `and/c` somehow merged the first-order checks of the > two rather than checking both separately).
:-) > It works if the two contracts mention exactly the same members. That's the useless case. So I guess we're really giving up something with opaque contracts. Since you're the one who created most and you don't seem to mind copying contracts, I am fine with opaqueness. I won't use it myself, however, when I write contracts for classes. I have found the above pattern too useful. -- Matthias _________________________ Racket Developers list: http://lists.racket-lang.org/dev
