Delphi tstream: weird creation behavior

Question

I am new to Delphi. In the documentation for the TStrem class, I read that it is an abstract class. So I think the compiler is wrong when I try to create it with

stream := TStream.Create();

Why not?

Answer 1

The Delphi language does not actually have a formal concept of an abstract class.

It is true that you can define a class as abstract:

type
  TMyClass = class abstract
  end;

But you can create an instance of this class. In fact, class abstractin Delphi it is a function used only by the long-abandoned Delphi.net compiler.

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