Why can I not convert from List<IScreen> to List<IRenderable> even when IScreen implements IRenderab

Posted by Blub on Stack Overflow See other posts from Stack Overflow or by Blub
Published on 2010-05-24T10:03:56Z Indexed on 2010/05/24 10:21 UTC
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c#

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interface

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contravariance

Pretty self explanatory question, glad for any answer. For me it doesn't make sense. I don't care about losing information. I just want to concatenate all my lists that inherit IRenderable somehow into a single list and then call IRenderable methods on it. I have a feeling that this is some basic rule of programming I forgot...

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