Traits, rôles and other repurposed terms

David Cantrell david at
Fri Feb 8 12:28:21 GMT 2008

On Thu, Feb 07, 2008 at 02:06:16PM -0600, Jonathan Rockway wrote:

> ... You can make your classes that do "equals" inherit from a
> superclass which implements "not_equals". ... [That] is a misuse of
> "isa"

To me, that just shows that "isa" should be pronounced "inherits from"
or "is derived from".  Or even, perish the thought, "extends" like in

Pronouncing it as "is a" works well when you're explaining OO to
newbies in terms of how physical objects like stools and chairs
"inherit" some of their characteristics from the superclass of "seats"
and others from, eg, "things made of wood", but thinking of classes
solely in terms of physical objects breaks down eventually.

David Cantrell | Official London Perl Mongers Bad Influence

    Safety tip: never strap firearms to a hamster

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