计算机专业英语 第章.ppt

ProfessionalEnglishinComputerField ChapterFiveProgrammingLanguages 内容 正文HistoryofProgrammingLanguagesObject orientedProgramming阅读材料IntroductiontoTheC LanguageandThe NETFrameworkIntroductiontoPython 1HistoryofProgrammingLanguages KeyWords punchcardn 穿孔卡片appearancen 外观decimaladj 十进位的formulaicadj 公式的Turingmachine图灵机magneticdrum磁鼓assemblylanguage汇编语言error prone易于出错的Backus NaurForm BNF BNF范式context free上下文无关lexicaladj 词汇的 语词的 KeyWords polymorphicadj 多形态的tediousadj 冗长乏味的defensecontractors国防承包商postulatev 假设compilationn 编译garbagecollection垃圾回收statictyping静态验证extendedstaticchecking延伸静态检查modularityn 模块mixinn 混合类型delegaten 委托punctuationn 标点符号 Notes Itsprincipaluseisinrigorousanalysesofalgorithmiccomplexity Theintroductionoflexicalscopingfornamesinarbitrarilynestedscopes However oneimportantnewtrendinlanguagedesignwasanincreasedfocusonprogrammingforlarge scalesystemsthroughtheuseofmodules orlarge scaleorganizationalunitsofcode 它主要应用在对算法复杂性的精密分析中 在任意嵌套中引入了变量名的语义 作用 范围 然而 语言设计的一个重要的新趋势是应用模块或大型企业级代码单元来开发大型系统已经成为关注的焦点 Notes Thelimitedspeedandmemorycapacityforcedprogrammerstowritehandtunedassemblylanguageprograms ThedesignofJavawasamoreconservativeversionofideasexploredmanyyearsearlierintheSmalltalkcommunity butthewidespreadadoptionoflanguagesthatsupportedfeatureslikegarbagecollectionandstrongstatictypingwasamajorchangeinprogrammingpractice 有限的速度和内存容量迫使程序员手工编写优化了的汇编程序 Java的设计比Smalltalk社区在很多年前就已经探索过的想法更保守 但是 对于支持垃圾回收和强静态类型等特性的编程语言的广泛采用是一个在实际编程中的主要变化 2Object orientedProgramming KeyWords object orientedadj 面向对象的paradigmn 范例inheritancen 继承modularityn 模块性polymorphismn 多态性encapsulationn 封装nascentadj 初期的virtuen 优点attributen 属性propertyn 属性behaviorn 行为 KeyWords featuren 特征jargonn 行话traitn 特性combinatorialadj 组合的extrapolationn 推断notionn 概念cementv 加强toolkitn 工具包 软件包event drivenprogramming事件驱动编程思想virtualmachine虚拟机 Notes Object orientedprogramming srootsreachallthewaybacktothecreationoftheSimulaprogramminglanguageinthe1960s whenthenascentfieldofsoftwareengineeringhadbeguntodiscusstheideaofasoftwarecrisis Object orientedprogrammingmaybeseenasacollectionofcooperatingobjects asopposedtoatraditionalviewinwhichaprogrammaybeseenasacollectionoffunctions orsimplyasalistofinstructionstothecomputer 面向对象编程的根源可以追溯到60年代出现的Simula编程语言 当时新生的软件工程界已经开始讨论软件危机了 面向对象的程序也许可以被看成一个由相互合作的对象组成的集合 而传统的看法则把程序看成由许多函数组成的集合 或是简单的计算机指令集合 Notes Aclassshouldtypicallyberecognizabletoanon programmerfamiliarwiththeproblemdomain meaningthatthecharacteristicsoftheclassshouldmakesenseincontext 一个类通常对于熟悉问题域的非程序员应当是可识别的 也就是说 类的特性在上下文中应该有意义的 ReadingMaterial1IntroductiontoTheC LanguageandThe NETFramework Exercises The wasanabstractionoftheoperationofatape markingmachine forexample inuseatthetelephonecompanies In1948 KonradZusepublishedapaperabouthisprogramminglanguage anearlysystemsprogramminglanguage wasdevelopedbyDennisRitchieandKenThompsonatBellLabsbetween1969and1973 The1960sand1970salsosawconsiderabledebateoverthemeritsof whichessentiallymeantprogrammingwithouttheuseof Inthe1980s oneimportanttrendinlanguagedesignwasanincreasedfocusonprogrammingforlarge scalesystemsthroughtheuseof or ofcode Object orientedprogramming OOP isaprogrammingparadigmthatuses todesignapplicationsandcomputerprograms isbehaviorthatvariesdependingontheclassinwhichthebehaviorisinvoked thatis twoormoreclassescanreactdifferentlytothesamemessage A definestheabstractcharacteristicsofathing includingthething scharacteristics itsattributesorproperties andthethingsitcando itsbehaviorsormethodsorfeatures questions Pleaselistatleast5kindsofprogramminglanguagesinthe1950sand1960s Brieflydescribefourkindsofmajorlanguageparadigmsnowinuseinthisperiodbetween1967and1978 Brieflydescribethegreatchangesofprogramminglanguagesinthe1980s HowdoestherapidgrowthoftheInternetinthemid 1990 sinfluencetheprogramminglanguage Givesomedirections