nheritance
Use message superclass: or subclass, as the above example shown. Many Smalltalk IDEs can generate code templates for class creation and other structures.
Method definition
A corresponding method gets executed when a message was sent to a receiver object. A method signature is a list of selector-parameter pair separated by spaces.
“define a method cube:, which take a parameter i”
cube: i
^i * i * I “^ means return to the caller”
Instance creation
Smalltalk class library use the message new to create an Instance of a class. You can define you own new method or you can define other names instead of new for instance creation.
aTree := BinaryTree new. “create an instance of class BinaryTree”