>>>>> "Hal" == Hal E Fulton <hal9000 / hypermetrics.com> writes:

    Hal> I'm probably being dense. The simple difference between
    Hal> "X is an instance of Y" and "X inherits from Y" confuses
    Hal> me.

Yeah, I hear you.

The instance-of hierarcy is differenct and separate from the
inherits-from hierarchy.  The fact that we tend to use "is-a" for both
makes it confusing.

Try this.  Draw a diagram of the major players (Object, Class, etc.).
Mark all the instance-of relationships with one color, and the
inherits-from relationships with another color.  Study the diagram
real hard.  Study it real hard.  When you are done, you probably won't
understand it any better, but you will have a cool diagram to hang on
your wall. :-)

-- 
-- Jim Weirich     jweirich / one.net    http://w3.one.net/~jweirich
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"Beware of bugs in the above code; I have only proved it correct, 
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)