Signature matching

signature.rb

class Signature
  def self.[] *sig
    Signature.new sig
  end

  def initialize sig
    @signature = sig
  end

  def === other
    return false if other.length != @signature.length
    
    
    @signature.zip(other).map { |match, argument|
      case match
      when Symbol; argument.respond_to? match
      else; match === argument
      end
    }.all?
  end
end

someclass.rb

def initialize *args
  @pointer = Native.ofimage_new

  case args
  when Signature[]
  when Signature[:to_s]
    load args.first
  when Signature[:to_f, :to_f]
    resize *args
  when Signature[:to_s, Fixnum, Boolean]
    file, quality, texture = args
    load file, quality
    use_texture texture
  else
    raise ArgumentError, args.inspect
  end
end