| Description |
The Exclude procedure excludes a set value from a set variable.
A set variable is one that can contain 0, some, or all values of a set. When you Exclude a set value in a set variable, you are removing from the included values in the variable.
Exclude is equivalent to the - operator, as shown here :
Exclude(CardHand, JackOfClubs);
CardHand := CardHand - [JackOfClubs];
For example, you can remove a playing card from a players hand - where the hand is based on a set of all playing cards in a deck.
Use Include to add a value to a set variable. This would, for example, allow a card to be added to a player's hand.
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| Related commands |
| In |
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Used to test if a value is a member of a set |
| Include |
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Include a value in a set variable |
| Set |
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Defines a set of up to 255 distinct values |
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| Example code : Creating a variable containing only positive numbers 0 to 10 |
// Full Unit code.
// -----------------------------------------------------------
// You must store this code in a unit called Unit1 with a form
// called Form1 that has an OnCreate event called FormCreate.
unit Unit1;
interface
uses
// The System unit does not need to be defined
SysUtils,
Forms, Dialogs;
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm} // Include form definitions
procedure TForm1.FormCreate(Sender: TObject);
var
evenNumbers : Set of 0..10;
i : Integer;
begin
// Make sure that evenNumbers only contains even numbers
evenNumbers := [0..10];
for i := 0 to 10 do
if (i mod 2) > 0
then Exclude(evenNumbers, i);
// Now display the set contents
for i := 0 to 10 do
if i in evenNumbers
then ShowMessage(IntToStr(i)+' is even');
end;
end.
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| Hide full unit code |
0 is even
2 is even
4 is even
6 is even
8 is even
10 is even
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