Introduction to Classes and Objects - Revision history

Thomas Linder Puls: categories

2021-04-12T13:48:58Z

Thomas Linder Puls: categories

2021-04-12T13:46:43Z

Thomas Linder Puls: line

2018-09-19T13:23:47Z

line

← Older revision		Revision as of 15:23, 19 September 2018
Line 217:		Line 217:
	When I want to implement the class user, I will, of course, like to take an advantage of one of our person classes. Let us assume that the user class should resemble the class person, except of course that it also deals with the password. I would like our class user to '''''inherit''''' the implementation of the person part from class person. This is achieved by the following code:		When I want to implement the class user, I will, of course, like to take an advantage of one of our person classes. Let us assume that the user class should resemble the class person, except of course that it also deals with the password. I would like our class user to '''''inherit''''' the implementation of the person part from class person. This is achieved by the following code:

	<vip>implement user		<vip>implement user inherits person
	inherits
	person

	facts		facts

Tbn: /* Inheritance */

2016-11-03T11:53:29Z

Inheritance

← Older revision		Revision as of 13:53, 3 November 2016
Line 275:		Line 275:
	*The person object is not embedded in the user object, instead there is a reference to it. (Also here there are two memory allocations instead of one).		*The person object is not embedded in the user object, instead there is a reference to it. (Also here there are two memory allocations instead of one).

	*In the last situation I can ''dynamically'' change the value in the fact variable to another object; simply by assigning a new object to the fact variable. For example, to an object of class personInDB.You should also notice that the second implementation have an extra level of indirection in the call. Visual Prolog handles such indirections rather ~~efficient~~, but it handles the inheritance even more ~~efficient~~.		*In the last situation I can ''dynamically'' change the value in the fact variable to another object; simply by assigning a new object to the fact variable. For example, to an object of class personInDB.You should also notice that the second implementation have an extra level of indirection in the call. Visual Prolog handles such indirections rather efficiently, but it handles the inheritance even more efficiently.

	Visual Prolog has multiple inheritance, meaning that you can inherit from many classes simultaneously.		Visual Prolog has multiple inheritance, meaning that you can inherit from many classes simultaneously.

Tbn: /* Supports (Type Extension) */

2016-11-03T11:51:27Z

Supports (Type Extension)

← Older revision		Revision as of 13:51, 3 November 2016
Line 207:		Line 207:
	*the objects of that type must provide all the predicates in the indirectly as well as directly supported interfaces		*the objects of that type must provide all the predicates in the indirectly as well as directly supported interfaces

	*the objects of that type have all the other indirect as well as direct ~~typesThe~~ supports qualifications generate a subtype hierarchy: we say that user is a subtype of person.		*the objects of that type have all the other indirect as well as direct types. The supports qualifications generate a subtype hierarchy: we say that user is a subtype of person.

	==Object: the Ultimate Object Super-Type==		==Object: the Ultimate Object Super-Type==

Tbn: /* Supports (Type Extension) */

2016-11-03T11:50:48Z

Supports (Type Extension)

← Older revision		Revision as of 13:50, 3 November 2016
Line 203:		Line 203:
	*the objects of that type must provide all the predicates in the supported interfaces		*the objects of that type must provide all the predicates in the supported interfaces

	*the objects of that type have all the other types as ~~wellAn~~ interface can also support one or more interfaces, which themselves support one or more interfaces, and so forth. And also in that case:		*the objects of that type have all the other types as well. An interface can also support one or more interfaces, which themselves support one or more interfaces, and so forth. And also in that case:

	*the objects of that type must provide all the predicates in the indirectly as well as directly supported interfaces		*the objects of that type must provide all the predicates in the indirectly as well as directly supported interfaces

Thomas Linder Puls: category

2016-03-04T10:25:41Z

Kari Rastas: /* Object Model */

2007-10-02T20:47:20Z

Object Model

← Older revision		Revision as of 22:47, 2 October 2007
Line 3:		Line 3:
	==Object Model==		==Object Model==

	The main semantic entities in the Visual Prolog [~~http~~:~~//en.wikipedia.org/wiki/~~Object_model object model] are [~~http~~:~~//en.wikipedia.org/wiki/~~Object_%28computer_science%29 objects], object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.		The main semantic entities in the Visual Prolog [[wikipedia:Object_model\|object model]] are [[wikipedia:Object_%28computer_science%29\|objects]], object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.

	An [~~http~~:~~//en.wikipedia.org/wiki/~~Interface_%28computer_science%29 interface] is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.		An [[wikipedia:Interface_%28computer_science%29\|interface]] is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.

	Consider this interface definition:		Consider this interface definition:

Kari Rastas at 08:59, 22 September 2007

2007-09-22T08:59:17Z

← Older revision		Revision as of 10:59, 22 September 2007
Line 3:		Line 3:
	==Object Model==		==Object Model==

	The main semantic entities in the Visual Prolog [http://en.wikipedia.org/wiki/Object_model object model] are [~~objects~~ http://en.wikipedia.org/wiki/Object_%28computer_science%29], object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.		The main semantic entities in the Visual Prolog [http://en.wikipedia.org/wiki/Object_model object model] are [http://en.wikipedia.org/wiki/Object_%28computer_science%29 objects], object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.

	An interface is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.		An [http://en.wikipedia.org/wiki/Interface_%28computer_science%29 interface] is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.

	Consider this interface definition:		Consider this interface definition:

Kari Rastas: Added a couple of external links

2007-09-22T08:56:50Z

Added a couple of external links

← Older revision		Revision as of 10:56, 22 September 2007
Line 3:		Line 3:
	==Object Model==		==Object Model==

	The main semantic entities in the Visual Prolog object model are objects, object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.		The main semantic entities in the Visual Prolog [http://en.wikipedia.org/wiki/Object_model object model] are [objects http://en.wikipedia.org/wiki/Object_%28computer_science%29], object types and classes. The main syntactic notions to deal with these entities are interfaces, class declarations and implementations.

	An interface is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.		An interface is a named set of predicate declarations. Interfaces describe the "interface" of objects (hence the name), i.e. the access that you have to an object from outside the object. Interfaces represent '''''object types'''''.

	Consider this interface definition:		Consider this interface definition:
Line 15:		Line 15:
	end interface person</vip>		end interface person</vip>

	This is the definition of an interface named person. All objects of the person type have two predicates getName and setName, with declarations as stated above.		This is the definition of an interface named person. All objects of the person type have two predicates getName and setName, with declarations as stated above.

	Interfaces only define types of objects; it is classes that create the objects. A class has a ''declaration'' and an ''implementation''. A class that ''constructs'' person objects, might be declared like this:		Interfaces only define types of objects; it is classes that create the objects. A class has a ''declaration'' and an ''implementation''. A class that ''constructs'' person objects, might be declared like this:

	<vip>class person : person		<vip>class person : person

← Older revision		Revision as of 15:48, 12 April 2021
Line 290:		Line 290:
	[[ru:Введение в Классы и Объекты]]		[[ru:Введение в Классы и Объекты]]
	[[Category:Tutorials]]		[[Category:Tutorials]]
			[[Category:Data types and handling]]

← Older revision		Revision as of 15:46, 12 April 2021
Line 289:		Line 289:

	[[ru:Введение в Классы и Объекты]]		[[ru:Введение в Классы и Объекты]]
	[[Category:~~Object system~~]]		[[Category:Tutorials]]

← Older revision		Revision as of 12:25, 4 March 2016
Line 289:		Line 289:
	*Object predicate values, a seamless counterpart to C# delegates.		*Object predicate values, a seamless counterpart to C# delegates.

	~~==References==~~
	[[ru:Введение в Классы и Объекты]]		[[ru:Введение в Классы и Объекты]]
	[[Category:~~Tutorials~~]]		[[Category:Object system]]