Lecture Notes for February 20

Read for Today

• Sections 3.5 and 3.6.

Topics to Cover Today

• Binding of referencing environments
  • dynamic versus static scope
  • subroutine closures
    • closure = code + environment
  • first-class subroutines
    • first-class = parameter, returned, local variable
    • static scope = defining environment has to come along!
• Binding within a scope
  • Stakeholders:
    • Who's responsible: programmer? compiler? runtime?
    • Who does it affect: programmer? compiler? runtime?
  • Options:
    • Aliases
    • Overloading
    • Polymorphism