MT2 review outline
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OOP
    class variables vs. instance variables
        is this variable specific to one object?
        does it apply to all objects of the class?
        if you change the variable, what should be affected?
        environment diagrams
    inheritance
        is-a vs. has-a relationships
            beagle should be a child of dog because a beagle is-a dog
            is a dog a beagle?  not necessarily!
        containers, inventory (has-a)
    calling methods from within an object
        own methods
            (ask self ...)
        parent's methods (if overridden by child)
            (usual ...)
        methods from other objects
            (ask obj ...)

DDP
    general idea: data instructs program what to do
        (see Fall 1997 Final, Q4)
    doesn't need to use tables, doesn't need to use put/get

MP
    going from above-the-line OOP to MP and vice-versa
    types that check for operations

conventional/explicit dispatch
    operators that check for types

environment diagramming examples