I agree with you except that has-a is as (or more) useful a tool for OO in modelling mode as is-a is. Therefore when used properly for modelling, has-a is heavily used.

However I'll agree that there is an awful lot of bad OO out there that overuses is-a.

In reply to Re^2: The world is not object oriented by tilly
in thread The world is not object oriented by tilly

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