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Dispose procedure

In unit System

Free dynamically allocated memory.

Declaration

pascal
procedure &Dispose(P: Pointer)

Description

The first form Dispose releases the memory allocated with a call to New. The pointer P must be typed. The released memory is returned to the heap.

The second form of Dispose accepts as a first parameter a pointer to an object type, and as a second parameter the name of a destructor of this object. The destructor will be called, and the memory allocated for the object will be freed.

Errors

An runtime error will occur if the pointer doesn't point to a location in the heap.

See also

Example: ex16

pascal
Program Example16;

{ Program to demonstrate the Dispose and New functions. }

Type SS = String[20];

     AnObj = Object
       I : integer;
       Constructor Init;
       Destructor Done;
       end;

Var
  P : ^SS;
  T : ^AnObj;

Constructor Anobj.Init;

begin
 Writeln ('Initializing an instance of AnObj !');
end;

Destructor AnObj.Done;

begin
  Writeln ('Destroying an instance of AnObj !');
end;

begin
  New (P);
  P^:='Hello, World !';
  Dispose (P);
  { P is undefined from here on !}
  New(T,Init);
  T^.i:=0;
  Dispose (T,Done);
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.