144 ;;Quote: PPL failed as an extensible language because the base language was preserved in the extensions

144+;;Quote: goal of extensible languages was to extend a base language into a natural representation for data, operations, and control of an application

144 ;;Quote: users need a large amount of effort and knowledge to extend a language significantly

145 ;;Quote: lesson of extensible languages: no simple statement to an unknowledgeable computer can alter its behavior in major ways