Ah! I see what you did there. And/c gives the result of the projection of the first contract to the second one. And/c is a weird duck, just in general.
I don't know if it is okay. :) Robby On Thu, Jan 18, 2018 at 8:01 AM, Phil Nguyen <philnguyen0...@gmail.com> wrote: > In this example, is it ok for `f`'s contract to be able to inspect argument > `x`? It's originally sealed with `α`, and the contract takes advantage of > the unsealing in `g`'s domain to inspect it. Sure the contract is a separate > party than `f`, but is this ok? > > (define/contract f > (parametric->/c > (α) > (α > ((and/c α (λ (x) (printf "inspect x: ~a~n" x))) . -> . any/c) . -> . > any/c)) > (λ (x g) (g x))) > > (f 42 add1) > > On Thursday, January 18, 2018 at 8:53:03 AM UTC-5, Robby Findler wrote: >> >> On Thu, Jan 18, 2018 at 7:43 AM, Phil Nguyen <philngu...@gmail.com> wrote: >> > It looks like a more general issue we have is that arguments are >> > sometimes >> > unexpectedly unsealed and prone to inspection by arbitrary code in >> > contracts, like `->i`'s range or a second conjunct to `and/c`. >> >> Well, they are supposed to be unwrapped when they pass "out". The ->i >> thing is a more general question of "where is 'out', anyway?" and I >> put to you that this isn't trivial (there are multiple papers on the >> topic already). >> >> Can you explain more what you mean about and/c, however? >> >> Robby > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
