module MongoMethodStorable

# File lib/mongo_method_storable.rb, line 7
def mongo_store(method_name)
  old_method_name = "#{MONGO_STORE_PREFIX + method_name.to_s}".to_sym
  raise AlreadyAliasedError.new("Already aliased #{method_name}") if method_defined?(old_method_name)
  alias_method old_method_name, method_name

  if instance_method(method_name).arity == 0
    define_method method_name do
      attr_val = read_attribute method_name
      return attr_val if attr_val
      attr_val = send old_method_name
      write_attribute(method_name, attr_val)
      save!
      attr_val
    end
  else
    # deal with this case when I need to
  end
end

# File lib/mongo_method_storable.rb, line 26
def storable_methods
  self.instance_methods.
    select {|m| self.instance_method(m).name.to_s.start_with? MONGO_STORE_PREFIX}.
    map {|m| m.slice(MONGO_STORE_PREFIX.length..m.length).to_sym}
end