SuperclassDelegatingAccessor

A Ruby utility that defines both class and instance accessors for class attributes. Creates private _attr and _attr= methods that can still be used if the public methods are overridden.

Add this line to your application's Gemfile:

gem 'superclass_delegating_accessor', '~> 0.0.1'

And then execute:

$ bundle

Or install it yourself as:

$ gem install superclass_delegating_accessor

class Person
  superclass_delegating_accessor :hair_colors
end

Person.hair_colors = [:brown, :black, :blonde, :red]
Person.hair_colors     # => [:brown, :black, :blonde, :red]
Person.new.hair_colors # => [:brown, :black, :blonde, :red]

If a subclass changes the value then that would also change the value for parent class. Similarly if parent class changes the value then that would change the value of subclasses too.

class Male < Person
end

Male.hair_colors << :blue
Person.hair_colors # => [:brown, :black, :blonde, :red, :blue]

To opt out of the instance reader method, pass instance_reader: false.

class Person
  cattr_accessor :hair_colors, instance_writer: false, instance_reader: false
end

Person.new.hair_colors = [:brown]  # => NoMethodError
Person.new.hair_colors             # => NoMethodError

Or pass instance_accessor: false, to opt out both instance methods.

class Person
  cattr_accessor :hair_colors, instance_accessor: false
end

Person.new.hair_colors = [:brown]  # => NoMethodError
Person.new.hair_colors             # => NoMethodError

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request