Composed

This is a small utility to help you define new types purely through composition. This way you can build all the small objects you want and put them together in a simple way.

#lib/report.rb
class Report
  def initialize(config, filter:, output_format:)
    @config = config
    @output_format = output_format
    @filter = filter
  end

# ... etc ...
end

#lib/json_report.rb
ImportantJSONReport = Composed(Report) do
  dependency(:output_format) { JSONFormatter.new }
  dependency(:filter) { ImportantStuffFilter.new }
end

#app/biz_report.rb
ImportantJSONReport.new(my_config).generate(data)

Add this line to your application's Gemfile:

gem 'composed'

And then execute:

$ bundle

Or install it yourself as:

$ gem install composed

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec 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/dr0verride/composed.