Impossible to use ref and out in Extension methods?

Posted by Hun1Ahpu on Stack Overflow See other posts from Stack Overflow or by Hun1Ahpu
Published on 2010-04-11T20:31:11Z Indexed on 2010/04/11 20:33 UTC
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extension-methods

Why is it forbidden to call Extension method with ref modifier?

This one is possible:

public static void Change(ref TestClass testClass, TestClass testClass2)
    {
        testClass = testClass2;
    }

And this one not:

public static void ChangeWithExtensionMethod(this ref TestClass testClass, TestClass testClass2)
    {
        testClass = testClass2;
    }

But why?

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