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planets

This is a simple example illustrating the basics of defining and using protocols and categories.

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

%versions

Start by loading the example:

logtalk_load(planets(loader)).

Compute the weight of the m1 object on Earth:

earth::weight(m1, W1).

<!-- W1 = 29.40. -->

Compare with the weight of the m1 object on Mars:

mars::weight(m1, W1).

<!-- W1 = 11.16. -->

Compute the weight of the m2 object on Earth:

earth::weight(m2, W2).

<!-- W2 = 39.20. -->

Compare with the weight of the m2 object on Jupiter:

jupiter::weight(m2, W2).

<!-- W2 = 92.48. -->