[PASCAL] Ordinal types

[CouldnoT]

Ordinal types

 

Ordinal types are integer values that use literal indications instead of numbers. For example, if we need to define language variables (Romanian/English/French) we could use the value 1 for Romanian, 2 for English, and 3 for French. Other programmers wouldn't know the values for 1, 2 and 3 unless they find comments with these values. It will be more readable if we do it with ordinal types as in the below example:

 

program OrdinalTypes;
{$mode objfpc}{$H+}
uses
 {$IFDEF UNIX}{$IFDEF UseCThreads}
 cthreads,
 {$ENDIF}{$ENDIF}
 Classes
 { you can add units after this };
type
 TLanguageType = (ltRomanian, ltEnglish);
var
 Lang: TLanguageType;
 AName: string;
 Selection: Byte;
begin
 Write('Please select Language: 1 (Romanian), 2 (English)');
 Readln(Selection);
 if Selection = 1 then
 Lang:= ltRomanian
 else
 if selection = 2 then
 Lang:= ltEnglish
 else
 Writeln('Wrong entry');
 if Lang = ltRomanian then
 Write('Cum te numești: ')
 else
 if Lang = ltEnglish then
 Write('What is your name: ');
 Readln(AName);
 if Lang = ltRomanian then
 begin
  Writeln('Salut, ' , AName);
  Write('Vă rugăm să apăsați tasta Enter pentru a închide');
 end
 else
 if Lang = ltEnglish then
 begin
 Writeln('Hello ', AName);
 Write('Please press enter key to close');
 end;
 Readln;
end.

 

Integer, character and Boolean types are ordinal types, while real numbers and strings are not.

Edited October 30, 2020 by CouldnoT

[CouldnoT]