WrapperBased

Wrapper Based DCI implementation in Ruby.

Installation

Add this line to your application's Gemfile:

gem 'wrapper_based'

And then execute:

$ bundle

Or install it yourself as:

$ gem install wrapper_based

Require DCI in your gems or save in your rails app as app/config/dci.rb:

require 'wrapper_based/dci'

Usage

Dijkstra data | Dijkstra test | Djikstra example:

require_relative 'dijkstra/data'

module CurrentIntersection
  def neighbors(manhattan:)
    east_neighbor = manhattan.east_neighbor_of(self)
    south_neighbor = manhattan.south_neighbor_of(self)
    [south_neighbor, east_neighbor].compact # excludes nil neighbors
  end
end

module DestinationNode
  def shortest_path(from:, within:)
    return [self] if equal? from
    FindShortest[to: self, from: from, city: within].path
  end
end

module Map
  def distance_between(a, b)
    @distances[Edge.new(a, b)]
  end

  def distance_of(path)
    GetDistance[within: self].of(path)
  end
end

class GetDistance < DCI::Context(:within)
  within.as Map

  def between(from, to)
    within.distance_between(from, to)
  end

  def of(path)
    path.reverse.each_cons(2).inject(0) { |total_distance, pair| total_distance + between(*pair) }
  end
end

class FindShortest < DCI::Context(:from, :to, :city)
  from.as CurrentIntersection
  to.as DestinationNode
  city.as Map

  def distance
    city.distance_of path
  end

  def path
    shortest_path_from_city_neighbors << @from
  end

  private

  def shortest_path_from_city_neighbors
    from.
      neighbors(manhattan: @city).
      map { |neighbor| to.shortest_path from: neighbor, within: @city }.
      min_by { |path| city.distance_of path }
  end
end

View more examples

Context methods

to_proc

Returns call method as a Proc.

['Card Wars', 'Ice Ninja Manual', 'Bacon'].map &GiftToy[gifter: 'Jake', giftee: 'Finn']

context[params,...]

Square brackets are alias for call method.

TransferMoney[from: source_account, to: destination_account][amount: 100]

Development

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.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/RichOrElse/wrapper-based.

License

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