re: Slides and Demos from BorCon

Panos Theofanopoulos — Thu, 23 Sep 2004 15:06:00 GMT

if elements is null then elements.Length does not throw an exception ?

re: Slides and Demos from BorCon

Chuck Jazdzewski — Thu, 23 Sep 2004 16:28:00 GMT

Even if it didn't you would crash on the very next line because 0 * 2 is still 0.

This code should read,

// ** hypothetical syntax from Danny Thorpe **

type
List<T> = class
private
FEements: array of T;
FCount: Integer;
function GetItems(index: Integer): T;
procedure SetItems(index: Integer; value: T);
public
procedure Add(element: T);
property Items[index: Integer]: T read GetItems write SetItems default;
property Count: Integer read FCount;
end;

procedure List<T>.Add(element: T);
begin
if not Assigned(FElements) then
SetLength(FElements, 4)
else if FElements.Length = FCount then
SetLength(FEements, FCount * 2);
FElements[FCount] := element;
Inc(FCount);
end;

function List<T>.GetItems(index: Integer): T;
begin
Result := FElements[index];
end;

procedure List<T>.SetItems(index: Integer; value: T);
begin
FElements[index] := value;
end;

var
intList: List<Integer>;
i: Integer;

begin
intList := List<Integer>.Create;
intList.Add(1); // No boxing
intList.Add(2); // No boxing
intList.Add(‘3’); // Compile-time error
i := intList[0]; // No cast required
end.

Staffan Malmgrens blogg » Blog Archive » Quickies of the day

Staffan Malmgrens blogg » Blog Archive » Quickies of the day — Tue, 24 Oct 2006 11:17:11 GMT

PingBack from http://externblog.tomtebo.org/2004/09/24/quickies_of_the_day-2