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carengines

For a description of this example, please see the comments in the carengines.lgt source file.

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

%versions

Start by loading the example:

logtalk_load(carengines(loader)).

Both cars provide the same interface, declared in the protocol that is implemented by the categories imported by each object.

Public predicates of the sedan object:

%%table
sedan::current_predicate(Predicate).

<!-- P = reference/1 ; P = capacity/1 ; P = cylinders/1 ; P = horsepower_rpm/2 ; P = bore_stroke/2 ; P = fuel/1 ; false. -->

Public predicates of the coupe object:

%%table
coupe::current_predicate(Predicate).

<!-- P = reference/1 ; P = capacity/1 ; P = cylinders/1 ; P = horsepower_rpm/2 ; P = bore_stroke/2 ; P = fuel/1 ; false. -->

The sedan engine properties are the ones defined in the corresponding imported category (classic):

sedan::(reference(Name), cylinders(Cylinders), horsepower_rpm(HP, RPM)).

<!-- Name = 'M180.940', Cylinders = 6, HP = 94, RPM = 4800. -->

The coupe engine properties are the ones defined in the corresponding imported category (sport) plus the ones inherited from the top category (classic) that are not overridden:

coupe::(reference(Name), cylinders(Cylinders), horsepower_rpm(HP, RPM)).

<!-- Name = 'M180.941', Cylinders = 6, HP = 115, RPM = 3657. -->