define_cached_method

# File activesupport/lib/active_support/code_generator.rb, line 15
      def define_cached_method(canonical_name, as: nil)
        canonical_name = canonical_name.to_sym
        as = (as || canonical_name).to_sym

        @methods.fetch(as) do
          unless @cache.method_defined?(canonical_name) || @canonical_methods[canonical_name]
            yield @sources
          end
          @canonical_methods[canonical_name] = true
          @methods[as] = canonical_name
        end
      end