A clojure/clojurescript library for asynchronous programming.
core.async is a clojure/clojurescript library to allow a model of asynchronous programming similar to that of the Go language.
Questions tagged [core.async]
229 questions
0
votes
1 answer
Sleeping barber in Clojure
I'm implementing Sleeping barber using core.async. My current code is:
(def workingtime 10000)
(defn barber [in waiting-room]
(go-loop [served-customers 0]
(let [[v] (alts! [waiting-room in])]
(if (= v :close)
…
Konstantin Milyutin
- 10,842
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1 answer
How to make manifold stream with dropping buffer?
Using core.async I'm able to easily create a channel with dropping buffer:
(async/chan (async/dropping-buffer 10))
Is it possible to create manifold stream with dropping buffer?
OlegTheCat
- 4,173
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- 22
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2 answers
How to prevent close!-ing before put-ing in onto-chan
I'd like to run a code like
(->> input
(partition-all 5)
(map a-side-effect)
dorun)
asynchronously dividing input and output(a-side-effect).
Then I've written the code to experiment below.
;; using boot-clj
(set-env! :dependencies…
ryo
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1 answer
Structuring clojure code with go blocks
I am using jet for asynchronous ring adapter.
Jet also comes with async http-client which returns a channel whose value's :body is also a channel.
Also, async server route handler can return a map whose :body key can contain a channel. When this…
Ashish Negi
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- 85
0
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1 answer
Putting then immediately removing value from channel causes weird behavior (ClojureScript core.async)
The following is a contrived example for learning purposes. It involves jamming the value "val" into a channel and then immediately removing it within a go block:
(def test-chan1 (chan))
(go
(println
(
George
- 5,909
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- 53
0
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2 answers
Placing a value at the bottom of a channel?
In Clojure(Script), is there anyway to jam a value at the bottom (as opposed to the top) of a channel so that the next time it is taken from (for example by using
George
- 5,909
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- 24
- 53
0
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2 answers
Clojurescript ajax.core without separate handler/callback, with very precise flow in the code as if the code was sync
In javascript I could write some code like:
var app_state={"context":"loading"};
$.get("")
.then(function(data){
app_state["data"]=data;
})
.then(change("context", "edit"))
.then(render)
In Clojurescript, I'd like something like:
(->…
Dan Bunea
- 167
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- 10
0
votes
1 answer
Idiomatic clojure: taking multiple items off a channel
I have a channel into which I am putting a number of individual values (JSON lines, incidentally).
In taking values off the channel, I wish to batch-process them as a group. Is there any notion of take n from the channel or else a means to bundle…
David
- 964
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- 14
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1 answer
Clojure - core.async interface for apache kafka
I am using clj-kafka, and I am trying to make a core.async interface to it in the REPL.
I am getting some messages, but my structure feels wrong : I either cannot stop receiving messages, or have to launch the go routine again to receive more…
nha
- 16,039
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0
votes
2 answers
When will channel be discarded when a thread keeps taking from it?
Consider the following piece of code taken from the example walkthrough of core.async:
(let [c1 (chan)
c2 (chan)]
(thread
(while true
(let [[v ch] (alts!! [c1 c2])]
(println "Read" v "from" ch))))
(>!! c1…
schaueho
- 3,269
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0
votes
2 answers
Multiple listeners / go blocks for channel in ClojureScript
Given a channel in ClojureScript
(def navigation (chan))
Is it possible to have multiple go blocks that pull values off it? E.g.
(go
(while true
(secretary/dispatch! (
Samuel
- 2,169
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- 35
0
votes
1 answer
core.async machine that loops until a fx returns true
While loading a web site, I often have the need to load code AFTER some other DOM structural event has occurred. Therefore I often end up with a lot of functions that first check if some element exist in the DOM and then do their thing in the event…
Stephen Cagle
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0
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1 answer
Performance counter for Clojure (using core.async)
I am wondering what is the best way to implement performance counters in Clojure for a particular task that runs concurrently.
I usually end up having something like this:
(defn -main [& args]
(let [c (async/chan)]
(doseq [_ (range 50)]
…
Istvan
- 6,372
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0
votes
1 answer
What is the idiomatic way to stop the event propagation with core.async (ClojureScript)?
I have a very simple use case: in a text area, I want to stop the event propagation for some key codes and trigger some function f, and for other key codes, I just trigger some function g.
So I've defined a channel called out and a listener, which…
Dr. Christian Müller
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0
votes
1 answer
Trying to create an asynchronous example using Core.Async.Pipe, but Pipe.write seems to block awaiting a Pipe.read
I've created the following toy example that counts in a loop and writes the value to an Async.Pipe:
open Sys
open Unix
open Async.Std
let (r,w) = Pipe.create ()
let rec readloop r =
Pipe.read r >>=
function
| `Eof -> return ()
| `Ok v ->…
aneccodeal
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