Re: C++ not OOP? (Was: Language Efficiency

[rmartin@rcmcon.com (Robert Martin)]

matt@physics2.berkeley.edu (Matt Austern) writes:

>I agree that "pure" is a loaded word and that we should stop using it.
>However, I do see the benefits of having a language where classes and
>basic built-in types and operating system resources are objects;
>languages like that make it much easier to treat things consistently.

Do you agree that a language in which *everything* is an object is
intrinsically more limited than a language in which the programmer
gets to decide what to put in an object and what to keep out?  Do you
also agree that programs designed for the first type of language can
be implemented in the second type, more easily that vice versa?  If
so, do you agree that the benefits of the first type automatically
transfer to the second type?

>A well-designed class hierarchy that includes the basic types and
>that's rooted in some class like Object or ANY can sometimes be quite
>useful.

Sometimes, although I generally prefer not to have a single root to
the inheritance tree.

>It's not foolish to make a distinction between languages that have
>that sort of hierarchy and that have a base class from which all
>classes inherit, and languages that don't.

Agreed.  

"Pure" is probably the
>wrong word to use for that distinction; can anyone suggest a better?

Sure.  Tree model languages have all objects rooted at some top level
object.  Forest model language can have many independent disconnected
inheritance hierarchies.

This is a nomenclature that has been used to describe class libraries.
I think it covers languages quite nicely too.

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