Sorry, I wasn’t clear. The chaperone/impersonate-async-channel functions are exported from racket/async-channel. The async-channel contracts, however, are exported from racket/contract.
> On Jan 15, 2015, at 14:41, Robby Findler <ro...@eecs.northwestern.edu> wrote: > > Just a small nit: why export that function from racket/contract and > not an async-channel library? > > Robby > > > On Thu, Jan 15, 2015 at 3:33 PM, Alexis King <lexi.lam...@gmail.com> wrote: >> As an update, I’ve made a bit more progress on this. I’ve implemented an >> impersonate-async-channel function, and I’ve actually included this in the >> exports from racket/contract. I also realized the blame information is >> correct, it works fine. Most of the other issues remain, as well as a few >> new questions: >> >> There is no impersonate-evt function, so I’m not sure that my implementation >> will work. What should I do about this? >> I’d assume this needs to be documented/tested as well. Where should those >> things be located? >> >> >> On Jan 14, 2015, at 23:44, Alexis King <lexi.lam...@gmail.com> wrote: >> >> Currently, async channels do not have contracts to check their contents. >> This is a problem for Typed Racket, and it prevents typed code from >> interacting with code that produces async channels. >> >> I started looking into how to add contracts to the language, and it seems to >> use the chaperones/impersonator system, as I suspected. However, async >> channels obviously cannot be impersonated, so I needed to implement that as >> well. >> >> I modified the async-channel struct to use generics to allow it to be >> impersonated or chaperoned, which I have exposed by implementing >> chaperone-async-channel. I then tried implementing async-channel/c. The >> internals of the contract system are a little beyond me, but I got a working >> solution by following the example of the box contracts. >> >> My work thus far can be found here: >> https://github.com/lexi-lambda/racket/commit/84b9f3604891f3f2061fb28ed4800af8afa4751b >> >> First of all, is this a correct approach? Have I done anything wrong, or >> should I have done anything differently? I didn’t find much documentation on >> the internals of either of these systems, so I mostly went about things as I >> found them. >> >> Second, obviously, not everything is implemented here. Among the additional >> necessary changes are: >> >> I need to implement support for impersonators and impersonator contracts >> (right now I’ve only bothered to do chaperones). >> I need to implement async-channel/c-first-order and >> async-channel/c-stronger. I can probably figure out the latter, but I’m not >> even sure what the former is supposed to do. >> I need to implement a wrap-async-channel/c macro for the export. I’m not >> sure how this works, either. From looking at wrap-box/c, it seems to add >> some syntax properties, but I’m not sure what they do or how they work. >> Somehow, the blame information has to be correct. Is that what the wrap >> function does? Or do the async-channel functions need to be updated to >> assign blame? >> >> >> I’d really like to get this working, and I think I’m close, but I’m a little >> inexperienced. I’d appreciate any help, even if it’s just pointing me in the >> right direction. >> >> Thanks! >> >> >> >> _________________________ >> Racket Developers list: >> http://lists.racket-lang.org/dev >> _________________________ Racket Developers list: http://lists.racket-lang.org/dev
