class Dry::Configurable::Extension

def included(klass)
  raise AlreadyIncludedError if klass.include?(InstanceMethods)
  super
  klass.class_eval do
    extend(ClassMethods)
    include(InstanceMethods)
    prepend(Initializer)
    class << self
      undef :config
      undef :configure
    end
  end
  klass.instance_variable_set(:@__config_extension__, self)
end