Why is covariance and contravariance supported only for interfaces, but not for classes?

Is this a fundamental limitation (I really don’t see it) or as Eric Lippert usually says: no one has proved that it is worth implementing a function?

+4

generics c # covariance contravariance

Pavel voronin May 15, '14 at 12:29

No one has answered this question yet.

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Source: https://habr.com/ru/post/1540697/

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