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function TypeOf (var x): PObjectType;
Returns a pointer to the VMT of an object type or variable. This pointer can be used to identify the type of an object.
TypeOf
can be applied to expressions of object type and to
object type names. In the former case, the actual type of
polymorphic objects is returned.
TypeOf
is a Borland Pascal extension.
program TypeOfDemo; type FooPtr = ^Foo; BarPtr = ^Bar; Foo = object { Has a VMT, though it doesn't } x: Integer; { contain virtual methods. } constructor Init; end; Bar = object (Foo) y: Integer; end; constructor Foo.Init; begin end; var MyFoo: FooPtr; begin MyFoo := New (BarPtr, Init); if TypeOf (MyFoo^) = TypeOf (Bar) then { True } WriteLn ('OK') end.