ruby interfaces example

interfaces.rb

module APIProfile
  def profile
    raise NotImplementedError.new("You must implement '#{__method__}'.")
  end
end

module APIAddress
  def address
    raise NotImplementedError.new("You must implement '#{__method__}'.")
  end
end

class APIProviderA
  include APIProfile
end

class APIProviderB
  include APIProfile
  include APIAddress
end

# ---

> APIProviderA.new.respond_to? :profile
 => true 

> APIProviderA.new.profile
NotImplementedError: You must implement 'profile'.
  
> APIProviderA.new.respond_to? :address
 => false