module Rbfs
  class Future < BasicObject
    def initialize(&callable)
      @thread ||= ::Thread.new { callable.call }
    end

    def value
      @thread.value
    end

    def inspect
      if @thread.alive?
        "#<Future running>"
      else
        value.inspect
      end
    end

    def method_missing(method, *args)
      value.send(method, *args)
    end

    def respond_to_missing?(method, include_private = false)
      value.respond_to?(method, include_private)
    end
  end
end