italoadler / at-at

Ahead-of-time function scheduler

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at-at

Simple ahead-of-time function scheduler. Allows you to schedule the execution of an anonymous function for a point in the future.

Basic Usage

First pull in the lib:

(use 'at-at)

Next, schedule the function of your dreams. Here we schedule the function to execute in 1000 ms from now (i.e. 1 second):

(at (+ 1000 (now)) #(println "hello from the past!"))

You can also schedule functions to occur periodically. Here we schedule the function to execute every second:

(every 1000 #(println "I am cool!"))

This can easily be stopped with cancel or its synonym stop:

(stop *1)

Finally, it's also possible to start a periodic repeating fn with an inital delay:

(every 1000 #(println "I am cool!") 2000)

Pools

at-at uses ScheduledThreadPoolExecutors behind the scenes which use a thread pool to run the scheduled tasks. There is a default pool which is created for you with (+ cpu-count 2) threads. However, you may create your own and run them separately.

For example, here we create a pool with 5 threads:

(def my-pool (mk-pool 5))

We can then use this pool to run our own periodic

(every 1000 #(println "I am super cool!") my-pool)

And then throw in our old friend running on the default pool:

(every 1000 #(println "I used to be cool until you made your own pool!"))

When necessary it's possible to stop and reset a given pool:

(stop-and-reset-pool! my-pool)

We can also stop and reset the default pool:

(stop-and-reset-pool!)

Install

Fetch at-at from github: https://github.com/overtone/at-at or pull from clojars: [overtone/at-at "0.0.1"]

History

at-at was extracted from the awesome music making wonder that is Overtone (http://github.com/overtone/overtone)

Authors

• Sam Aaron
• Jeff Rose

(Ascii art borrowed from http://www.sanitarium.net/jokes/getjoke.cgi?132)