Covariance and contravariance are precise terms that describe which conversions are safe on parameters and return types. Learn practical definitions for those terms, what new constructs will be ...

The C# programming language provides excellent support for working with collections of data. C# includes several classes and interfaces that can help you query collections of data efficiently. The ...

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: ...