Re: Why are there no covariant return types?

From: Stefan Slapeta (stefan_nospam__at_slapeta.com)
Date: 07/02/04 

Date: Fri, 02 Jul 2004 11:35:57 +0200

Stoitcho Goutsev (100) [C# MVP] wrote:

> Yeah, besides the fact that theoretically you don't know the type of the
> object, which Clone methods you call.
>
> And again in theory one should go with the most generic base type and then
> do the conversion.
>

In theory, you should avoid any cast if possible because every cast is a
potential runtime error!

And here - *with* covariant return types - you *for sure* know what
class you are dealing with *and* you can avoid any cast.

ArrayList original;
ArrayList copy = original.Clone();

Stefan

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