This code actually results in a subtle race condition as channels need to be locked internally. It also won't work for other implementations of channel, of which there are several in core.async besides ManytoManyChannel. (For example, map< returns a reified channel.) Knowing whether a channel is closed at put-time (with some restrictions) is a current work item in core.async.
On Monday, January 13, 2014 5:12:58 AM UTC-5, t x wrote: > > (let [c (async/chan 10)] > (println @(.-closed c)) > (async/close! c) > (println @(.-closed c))) > > > And we're done. Sorry for the spam. Last message send in case someone > finds my question via Google. > > > On Mon, Jan 13, 2014 at 2:11 AM, t x <[email protected] <javascript:>>wrote: > >> Is there anyway, to "pierce the deftype" >> >> >> https://github.com/clojure/core.async/blob/master/src/main/clojure/clojure/core/async/impl/channels.clj#L31 >> >> to read the "closed" field of the ManytoMany Channel? >> >> That's basically all I need to do. >> >> >> On Mon, Jan 13, 2014 at 1:47 AM, t x <[email protected] <javascript:>>wrote: >> >>> Hi, >>> >>> I have the following problem: >>> >>> I have a set of channels #{ ... } >>> >>> some of the channels are closed, some of the channels are open >>> >>> * for the channels that are open, I want to (>! chan msg) >>> >>> * for the channels that are closed, I want to remove the channel from >>> the hash-set >>> >>> >>> ## Problems: >>> >>> (1) (>! ... ...) always returns nil, regardless of whether the channel >>> is open or closed, and thus useless >>> >>> (2) I could use (<! ... ) to read from the channel to see if it's nil, >>> but then would remove an item from the channel, which I don't want to do >>> >>> >>> ## Question: >>> >>> Thus, without changing the state of the channel, is there a way to see >>> if the channel is open/closed? >>> >>> Thanks! >>> >> >> > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to [email protected] Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
