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elephants

This is a simple example illustrating the concept of prototypes using elephants. A similar example is often found in knowledge representation discussions.

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Start by loading the example:

logtalk_load(elephants(loader)).

Prototypes are neither instances or classes but either standalone objects as clyde, our prototypical but concrete elephant:

clyde::number_of_legs(N).

clyde::color(C).

Or objects that are derived from other prototypes as fred, which is like clyde except in his color:

fred::number_of_legs(N).

fred::color(C).