acts_as_interface

INSTALL

gem install acts_as_interface

DESCRIPTION

In the spirit of self documenting code, acts_as_interface allows you to easily define abstract_methods and callbacks just by listing them at the top of a superclass or module. Child classes or classes that include the module must implement abstract_methods or a NotImplementedError is raised when the method is called.

EXAMPLES

SUPERCLASS

class Person
  include acts_as_interface

  abstract_methods :dance, :eat
  abstract_methods :sleep, :play, :visibility => :private
  callbacks :prance

  abstract_methods :foo, :for => :class
  callbacks :france, :for => :class, :visibility => :protected
end

class Student < Person

end

me = Student.new
me.dance ## => raises NotImplementedError

me.play ## => raises NoMethodError: private method `play` called
me.send(:play) ## => raises NotImplementedError

me.prance ## calls empty method prance

Student.foo ## => raises NotImplementedError

MODULE (on include)

module ActsAsPerson    
  def self.included(base)
    base.instance_eval do
      include ActsAsInterface
      abstract_methods :name, :dance
    end
  end
end

class Student < ActiveRecord::Base
  include acts_as_person

  #name is an attribute (ie t.string :name)
end

student = Student.first
student.name ## works as usual
student.dance ## => raises NotImplementedError

MODULE (from method call)

module ActsAsPerson    
  module ClassMethods
    def acts_as_person
      include ActsAsInterface
      abstract_methods :name, :dance
    end
  end

  def self.included(base)
    base.extend(ClassMethods)
  end
end

class Student < ActiveRecord::Base
  include acts_as_person

  #include or invoke modules that defines name but not dance

  acts_as_person ## apply interface
end

student = Student.first
student.name ## works as usual
student.dance ## => raises NotImplementedError

Credits

BookRenter.com Logo

ActsAsInterface is currently maintained by Philippe Huibonhoa and funded by BookRenter.com.

CONTRIBUTING

Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
Fork the project
Start a feature/bugfix branch
Commit and push until you are happy with your contribution
Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.