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roots

This folder contains rewritten versions of some objects provided with previous, 1.x versions, of Logtalk. They are intended to help the conversion of applications from Logtalk 1.x to 2.x and to support most of the other examples provided with the current Logtalk distribution.

Short description of each example entity:

[99, 108, 97, 115, 115]

default metaclass for all classes

[99, 108, 97, 115, 115, 112]

protocol of class class

[97, 98, 115, 116, 114, 97, 99, 116, 95, 99, 108, 97, 115, 115]

default metaclass for all abstract classes

[97, 98, 115, 116, 114, 97, 99, 116, 95, 99, 108, 97, 115, 115, 112]

protocol of class abstract_class

[111, 98, 106, 101, 99, 116]

root class for class-based hierarchies

[111, 98, 106, 101, 99, 116, 112]

protocol of class object

[105, 110, 105, 116, 105, 97, 108, 105, 122, 97, 116, 105, 111, 110]

category defining methods for object initialization

[112, 114, 111, 116, 111]

root prototype for prototype-based hierarchies

[112, 114, 111, 116, 111, 112]

protocol for prototype proto

[110, 105, 108]

object used to represent a void reference

Please note that the entities above are just example definitions. There is nothing fundamental about any of them; they can and should be replaced by definitions better fitted to the requirements of specific applications.

For a simpler version of this example, see the reflection example. If you are not familiar with the concept of metaclass used in this example, see the metaclasses example first.

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

%versions

Start by loading the example and the required library files:

logtalk_load(roots(loader)).

Some queries dealing with instance/class hierarchies:

abstract_class::ancestors(Ancestors).

class::ancestors(Ancestors).

object::ancestors(Ancestors).

class::instances(Instances).

class::superclass(Super).