hash_digger.rb

require "delegate"

class HashDigger < SimpleDelegator
  def method_missing(method_sym, *arguments, &block)
    if __getobj__.has_key?(method_sym)
      value = __getobj__[method_sym]

      if value.is_a?(Hash)
        self.class.new(value)
      else
        value
      end
    else
      super
    end
  end

  def respond_to?(method_sym, include_private = false)
    __getobj__.has_key?(method_sym) || super
  end
end


obj = HashDigger.new({ key1: { key2: [1, 2, 3] } })

puts obj.key1.key2[2]