Use "as" operator (USEAS)

Description:

Delphi allows you to replace the type check (is) and type cast operators with the single as operator. This makes the code clearer and improves performance.

Incorrect:

var str:String;
...
if obj is String then
begin
    str := String(obj);
    result := str.Length;
end;

Correct:

var str:String;
...
str := obj as String;
if str <> nil then
    result := str.Length;
end;