Pascal Programming/Object oriented

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Object Oriented Pascal allows the user to create applications with Classes and Types. This saves the developer time on developing programs that would be very flexible.

This is a sample program (tested with the FreePascal compiler) that will store a number 1 in private variable One, increase it by one and then print it.

 program types;  // this is a simple program
 type MyType=class
       private
        One:Integer;
       public
        function Myget():integer;
        procedure Myset(val:integer);
        procedure Increase();
      end;
 
 function MyType.Myget():integer;
 begin
   Myget:=One;
 end;
 procedure MyType.Myset(val:integer);
 begin
   One:=val;
 end;
 procedure MyType.Increase();
 begin
   One:=One+1;
 end;
 
 var
   NumberClass:MyType;
 begin
   NumberClass:=MyType.Create;  // creating instance
   NumberClass.Myset(1);
   NumberClass.Increase();
   writeln('Result: ',NumberClass.Myget());
   NumberClass.Free;  // destroy instance
 end.

This example is very basic and would be pretty useless when used as OOP. Much more complicated examples can be found in Delphi and Lazarus which include a lot of Object Oriented programming.