Case Study Designing the Palm Pilot

Why use Tools (rather than code)?FasterEasier to incorporate test changesMultiple UIs for same applicationConsistent user interfacesEasier to involve variety of specialistsSeparation of UI code from app. codeeasier to change/maintainMore reliableUser Interface DevelopmentEnvironmentsSpecification MethodsProgramming Support ToolsDesign Tools for Evaluating andCritiquingSpecification MethodsNatural LanguageFormal, Semi-Formal LanguageMultiparty GrammarsMenu TreesTransition DiagramsState ChartsUser Action NotationNatural LanguageSpecifications tend to be:lengthyvagueambiguousOften are difficult to prove:correctconsistentcompleteBackus-Naur Forma.k.a. Backus Normal Form/BNFHigh-level components are described asnon-terminalsSpecific strings are described asterminalsGrammars Example::= ::= , ::= ::= ::= | ::= A - Z::= () -::= ::= ::= ::= 0|1|2|3|4|5|6|7|8|9Examples of acceptable entries- WASHINGTON, GEORGE (301)555-1234- BEEF, STU (726) 768-7878- A, Z (999) 111-111BNF ExampleUnix Command-Copying Files (cp)cp [ -ip ] filename1 filename2cp -rR [ -ip ] directory1 directory2cp [ -iprR ] filename ... directory[ ]'s = 0 or more timesMultiparty GrammarsSpecify a role (U=user, C=Computer) ::= ::= login ::= ::= Hello []login larryHello larry