In the first case, there is a strong upward-sloping relationship between X and Y; in the second case, no apparent relationship; in the third case, a strong downward-sloping relationship. Note the ...

Understanding type compatibility is fundamental to writing good Java programs, but the interplay of variances between Java language elements can seem highly academic to the uninitiated. This article ...

You can use covariance and contravariance to provide polymorphic extension to delegates, arrays, and generics in C#. Here’s how. The C# programming language provides support for variance in two ways: ...