Table of ContentsSmalltalk and pure object oriented programming OO Focuses on the Data Pure Object-Orientation: Everything is an object More about objects What is a class? Classes are also objects! Example Diagram of Ball class and its instances Everything is an object! is-instance-of relationship is-a relationship Object hierarchy Computation via messages and methods Object-oriented vs. procedural terminology Smalltalk-80 Features of Smalltalk-80 Smalltalk Class Browser Class Hierarchy Pane The Class Hierarchy Navigator Variables Pane A Filter for the Methods Pane Methods Pane A Listing of the Relevant Methods Method Definition Window So where’s my program? Filing out your code Filing in code Asking questions about code Learning more about Smalltalk/Express Environment Simple Smalltalk Syntax More Smalltalk Syntax Stack Object Implementing a Stack ADT Stack Object Methods Adding a subclass Adding a class method Adding an instance method More stack methods Shared Variables Private variables Variables Constructing a Stack Object construction in Smalltalk Initializer method Common mistakes Errors… Superb Debugger! Message terminology Three kinds of Messages Parsing Messages Parsing keyword messages The importance of the colon: Cascading messages Message dispatch Dispatch examples Method terminology Dispatch algorithm Talking to yourself Smalltalk schizophrenia Writing draw without message dispatch So what’s the big deal? Modularity Overriding a method Replacing a method A less drastic change in behaviour Do not duplicate code! Getting help from your parent super keyword Example of super Sample message sends A small change More message sends Recursion Conditionals Blocks ? Scheme’s lambda Blocks package up code Class Boolean Class Boolean has no state! While loops Common mistakes Collection classes Collections understand lots of messages... do: and collect: messages Dictionary class The Smalltalk object Smalltalk summary |
Author: Greg J. Badros
Email: badros@cs.washington.edu Home Page: http://www.cs.washington.edu/education/courses/341/CurrentQtr |