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Smalltalk Design Choices

• Type Checking and Polymorphism
  • All bindings of messages to methods is dynamic
  • The process is to search the object to which the message is sent for the method; if not found, search the superclass, etc.
  • Because all variables are typeless, methods are all polymorphic

• Inheritance
  • All subclasses are subtypes (nothing can be hidden)
  • All inheritance is implementation inheritance
  • No multiple inheritance
  • Methods can be redefined, but the two are not related