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Last active July 4, 2021 13:52
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(ns async-test.throttle.core
(:require [cljs.core.async :refer [chan close!o sliding-buffer]]
[clojure.string :as string])
(:require-macros
[cljs.core.async.macros :as m :refer [go alts!]]))
(def c (chan (sliding-buffer 1)))
(def loc-div (.getElementById js/document "location"))
(.addEventListener js/window "mousemove"
(fn [e]
(go
(>! c [(.-x e) (.-y e)]))))
(defn timeout [ms]
(let [c (chan)]
(js/setTimeout (fn [] (close! c)) ms)
c))
(defn throttle [c ms]
(let [c' (chan)]
(go
(while true
(>! c' (<! c))
(<! (timeout ms))))
c'))
(def throttled (throttle c 500))
(go
(while true
(let [loc (<! throttled)]
(aset loc-div "innerHTML" (string/join ", " loc)))))
@thheller
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This code produces javascript errors when I move the mouse (Chrome).

It works when switching c to (def c (chan (async/sliding-buffer 1))) . I guess "pausing" doesn't quite work yet (in the CLJS implementation) otherwise (>! c [x y]) would "pause" until the event is consumed, which only happens every 500ms.

@swannodette
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@lynaghk @thheller I made an error, I should have created a chan with a sliding-buffer, updated.

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