class Options
  def initialize(*opts)
    @opts = opts
    vals = {}
    class <<self; self end.class_eval do
      opts.each do |opt|
        define_method(opt) do |*args|
          if args.size == 0
            vals[opt]
          else
            vals[opt] = *args
          end
        end
      end
    end
    @vals = vals
  end

  def run(&blk)
    instance_eval &blk
    self
  end

  def to_a
    @vals.values_at(*@opts)
  end
end

class YourClass
  def initialize
    @price = {}
  end

  def set_price(&blk)
    @price[:apples], @price[:oranges] = *Options.new(:apples,:oranges).run(&blk)
    self
  end
end

YourClass.new.set_price do
  apples 5
  oranges 2
end