alda-clj

A Clojure library for live-coding music with Alda.

Background and rationale

See History for a long-winded account of the path that led to alda-clj.

How does it work?

alda-clj is a Clojure DSL that is almost identical to the alda.lisp DSL built into the runtime of Alda 1.x. But instead of being part of the process that generates and plays the Alda score, alda-clj generates a string of Alda code and sends it to the alda client.

The idea is simple: alda is just a low-level tool for playing a score that's already been written (or generated). When you want to go higher-level and create scores programmatically, you can do so in an external process and pipe the result to alda. alda-clj is one way to do this.

alda-clj is intended to be used in at least two ways:

1. In an improv / live-coding setting, using a live Clojure REPL to generate and play music on the fly.

2. In a music composition setting, where the composition is a Clojure program / script that uses alda-clj to generate a score.

Usage

1. If you haven't already, install Alda and make sure alda is available on your PATH.

alda-clj will shell out and use alda (wherever it's found on your PATH) to play your scores. If desired, you can specify an alternate alda executable by binding alda.core/*alda-executable* to something else, e.g. "/home/dave/Downloads/some-other-alda".

2. Add the latest release version of alda-clj to your dependencies:

;; deps.edn
io.djy/alda-clj {:mvn/version "X.X.X"}

;; lein/boot
[io.djy/alda-clj "X.X.X"]

3. Require alda.core and you're off to the races!

(require '[alda.core :refer :all])

(play!
  (part "piano")
  (for [notes [[:c :e :g] [:c :f :a] [:c :e :g]]]
    (apply chord (map #(note (pitch %)) notes))))

Docs, examples, etc.

API documentation, a Getting Started guide and more are available at cljdoc.

There are also example scripts in this repo that will give you a sense of what you can do with alda-clj.

Ping @dave on Slack if you have any questions or if you just want to chat about alda-clj!

License

Copyright © 2018 Dave Yarwood

Distributed under the Eclipse Public License version 2.0.