alda-rb

A Ruby library for live-coding music with Alda. Also provides an alda DSL in Ruby.

Add this line to your application's Gemfile:

gem 'alda-rb'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install alda-rb

Install Alda, and try the following Ruby codes yourself:

require 'alda-rb'

puts Alda.version

score = Alda::Score.new { o4; c4/e/g; -d8; r8_16; +f4; o5; c2 }

Alda::Score.new do
  piano_
  quant 200
  v1
  5.times do |t|
    transpose t
    import score
    note midi_note(30 + t * t), duration(note_length 1)
  end
  v2; o6
  motif = -> { c200ms; d500ms }
  8.times { motif * 2; e400ms_4; t4 { a; b; c } }
  _ended
  
  violin_
  __ended
  ->i do
    c2; d4; e2_4; e2; d4; c2_4; c2; e4; d2
    i == 0 ? (c4; d1_2) : (d4; c1_2)
  end * 2

end.play

There is also an interactive mode. You can run it by running alda-irb in your command line if you installed the gem. Run bundle exec alda-irb instead if you installed it using the bundler.

$ alda-irb
> p processes.last
{:id=>"dus", :port=>34317, :state=>nil, :expiry=>nil, :type=>:repl_server}
> piano_; c d e f
piano: [c d e f]
> 5.times do
.   c
>   end
c c c c c
> score_text
piano: [c d e f]
c c c c c
> play
Playing...
> save 'temp.alda'
> puts `cat temp.alda`
piano: [c d e f]
c c c c c
> system 'rm temp.alda'
> exit

You can also use it to programmatically communicate with the nREPL server:

repl = Alda::REPL.new
repl.message :eval_and_play, code: 'piano: c d e f' # => nil
repl.message :eval_and_play, code: 'g a b > c' # => nil
repl.message :score_text # => "piano: [c d e f]\ng a b > c\n"
repl.message :eval_and_play, code: 'this will cause an error' # (raises Alda::NREPLServerError)

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/UlyssesZh/alda-rb. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the alda-rb project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.