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inheritance

This folder contains examples of public, protected, and private inheritance, for both prototype-based and class-based hierarchies.

This example defines a category named predicates which specifies three predicates, one public, one protected, and one private. This category is imported by the root objects: parent for the prototype hierarchy and root for the class hierarchy. Each root object have a set of three descendants, each one using one of the inheritance types.

The two object hierarchies are organized as follows:

parent
        prototype1				% public inheritance
                descendant1
        prototype2				% protected inheritance
                descendant2
        prototype3				% private inheritance
                descendant3

root
        subclass1				% public inheritance
                instance1
        subclass2				% protected inheritance
                instance2
        subclass3				% private inheritance
                instance3

A second category named interface, imported by all objects except the sub-class instances, allows us to query the objects about their interfaces.

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

%versions

Start by loading the example:

logtalk_load(inheritance(loader)).

parent interface:

parent::interface.

<!-- public/0 - public protected/0 - protected private/0 - private

true. -->

prototype1 extends `public::parent`:

prototype1::interface.

<!-- public/0 - public protected/0 - protected

true. -->

prototype2 extends `protected::parent`:

prototype2::interface.

<!-- public/0 - protected protected/0 - protected

true. -->

The prototype3 prototype extends `private::parent`:

prototype3::interface.

<!-- public/0 - private protected/0 - private

true. -->

The descendant1 prototype extends `public::prototype1`:

descendant1::interface.

<!-- public/0 - public protected/0 - protected

true. -->

The descendant2 prototype extends `public::prototype2`:

descendant2::interface.

<!-- public/0 - protected protected/0 - protected

true. -->

The descendant3 prototype extends `public::prototype3`

descendant3::interface.

<!-- true. -->

Object (root of the inheritance graph) interface:

root::interface.

<!-- public/0 - public protected/0 - protected private/0 - private

true. -->

instance1 instantiates subclass1 that specializes `public::root`:

instance1::interface.

<!-- protected/0 - protected public/0 - public

true. -->

instance2 instantiates subclass2 that specializes `protected::root`:

instance2::interface.

<!-- protected/0 - protected public/0 - protected

true. -->

instance3 instantiates subclass3 that specializes `private::root`:

instance3::interface.

<!-- true. -->