Destructor: what changed

Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.

Title: Destructor

New		Line
1	+	The [[Reserved word\|reserved word]] `destructor` belongs to [[object-oriented programming]]. The destroyer is used to release resources like memory. The destroyer must always be made so that when the memory is released, the memory used by the entire [[Class\|class]] (object) is released and therefore no memory leak occurs.
2	+
3	+	Release of the object takes place by calling a class `free` [[Method\|method]]. Calling `free` causes a `Destroy` invitation. It also checks that the [[Self\|self]] [[Variable\|variable]] is not [[Nil\|nil]].
4	+
5	+	for example:
6	+
7	+	``` pascal
8	+	program Project1;
9	+	{$ mode objfpc} {$ H +}
10	+
11	+	type
12	+
13	+	// class definition
14	+	{TClass}
15	+
16	+	TClass = Class
17	+	constructor Create;
18	+	destructor Destroy; override; // allows the use of a parent class destroyer
19	+	end;
20	+
21	+	// class builder
22	+	constructor TClass.Create;
23	+	begin
24	+	Writeln ('Build object');
25	+	end;
26	+
27	+	// class eraser
28	+	destructor TClass.Destroy;
29	+	begin
30	+	Writeln ('Demolished Object');
31	+	inherited; // Also called parent class destroyer
32	+	end;
33	+
34	+	var
35	+
36	+	// Defines the class variable
37	+	myclass: TClass;
38	+
39	+	begin
40	+	myclass: = TClass.Create; // Initialize the object by calling the class builder
41	+	Writeln ('Something Code ...');
42	+	myclass.Free; // Free invites your own class Destroy discharger
43	+	Writeln ('Press <Enter>');
44	+	readln;
45	+	end.
46	+	```
47	+
48	+	---
49	+	From the Free Pascal wiki, page "Destructor", as it stood on 2022-08-06 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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