How to use the scope method parameters?

I have a parsing gem option that provides DSL for creating commands. In practice, it often looks like this:

option :ints,    Integer, arity: [1, -1], on_multiple: :append
option :floats,  Float,   arity: [1, -1], on_multiple: :append
option :complex, Complex, arity: [1, -1], on_multiple: :append

These are class methods. Not very DRY, as you can see. It would be better to write something like this:

scope arity: [1, -1], on_multiple: :append do
  option :ints,    Integer
  option :floats,  Float
  option :complex, Complex
end

So that the hash parameters provided scopeare transparently merged with the parameter specified in option. This is where I am stuck. I am not sure where to store the general parameters so that I can combine them later.

Any ideas?

optionredirects everything to Option#new:

def option(*args, &block)
  # self is a class that represents a command
  self.options << Option.new(*args, &block)
end

As requested here, the code using the supported stones has been removed:

def initialize(key, *args, &block)
  # Retrieve the options hash from the argument array.
  options = args.last.is_a?(Hash) ? args.pop : {}

  # The rest of the implementation...
  type = args.find { |arg| arg.is_a? Module }

  strings = args.flatten.select do |arg|
    arg.is_a? String
  end.group_by do |arg|
    arg =~ Parser::Regexp::SWITCH ? :switches : :description
  end

  self.key = key
  self.names = strings.fetch(:switches) { [ Option.name_from(key) ] }
  self.description = options.fetch :description, strings.fetch(:description, []).first
  self.on_multiple = options.fetch :on_multiple, :replace
  self.arity = options.fetch :arity, nil
  self.default = options.fetch :default, nil
  self.required = options.fetch :required, false
  self.type = type || String
  self.handler = block
end

Original on GitHub .