Covariance and contravariance in programming languages

Posted by xdevel2000 on Stack Overflow See other posts from Stack Overflow or by xdevel2000
Published on 2009-07-22T06:49:10Z Indexed on 2010/03/31 21:43 UTC
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java

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c#

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c++

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programming-languages

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covariance

Can anyone explain me, the concept of covariance and contravariance in programming languages theory?

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