10 ;;Quote: reusable software should allow same-as-except as well as use-as-is; maintenance becomes a cycle of design refinements

10 ;;Quote: frame is a formalization of same-as-except since it accommodates variations

10 ;;Quote: a program is a tree of specification frames which decompose the program into customizations of other frames; 10% of source code

10 ;;Quote: a template specification frame defines a default frame composition and important options with explanations

11 ;;Quote: customize frames by breaks; slots which can receive frame text from any parent frame

11 ;;Quote: a select frame stores predefined variations, e.g., for converting dates

11 ;;Quote: with frames, most errors are in the customized specification frames because the underlying frames are robust