Deconstructable

This gem provides Deconstructable, a mixin module that helps you to support pattern-matching over your types.

Installation

Add this line to your application's Gemfile:

gem 'deconstructable'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install deconstructable

Usage

class Thing
    include Deconstructable

    ...

    # Mark some methods as deconstructable
    deconstructable :x, :y

    # Shortcut for attr_reader + deconstructable
    attr_deconstructable :readable_and_matchable

    # Using deconstructable as a method modifier
    deconstructable def foo
      do_the_foo
    end
end

This class provides a single DSL method deconstructable which helps you to mark methods and attributes as deconstructable. Deconstructable attributes will be made available in pattern matching, e.g.:

thing in Thing(foo:, x: 100, y:)

Classes that include Deconstructable gain an implementation of deconstruct_keys that permits hash-style key based pattern matching. Positional array-style patterns are not supported. All deconstructable methods must support being called with no parameters.

Development

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.

This Gem requires the new pattern matching features introduced in Ruby 2.7.0, so we need at least that version. I use asdf, and have supplied a suitable .tool-versions file. You can use this, or any other Ruby version manager.

Contributing

Bug reports and pull requests are welcome on GitLab at https://gitlab.com/alexkalderimis/deconstructable. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

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

Code of Conduct

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