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Hands-On Reactive Programming with Clojure - Second Edition
book

Hands-On Reactive Programming with Clojure - Second Edition

by Konrad Szydlo, Leonardo Borges
January 2019
Intermediate to advanced content levelIntermediate to advanced
298 pages
7h 46m
English
Packt Publishing
Content preview from Hands-On Reactive Programming with Clojure - Second Edition

Combinators and event handlers

Let's say we would like to double the value in the age future. As we do with lists, we can simply map a function over the future to do just this:

(def double-age (i/map age #(* % 2))) 
;; #<Future@659684cb: #<Success@7ce85f87: 62>> 
While i/future schedules its body for execution on a separate thread, it's worth noting that future combinators such as map, filter, and so on, do not create a new thread immediately. Instead, they schedule a function to be executed asynchronously in the thread pool once the original future completes.

Another way to do something with the value of a future is to use the on-success event handler that gets called with the wrapped value of the future if it is successful:

(i/on-success ...
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Publisher Resources

ISBN: 9781789346138Supplemental Content