Does the C# 4.0 “dynamic” keyword make Generics redundant?

Question

I\'m very excited about the dynamic features in C# (C#4 dynamic keyword - why not?), especially because in certain Library parts of my code I use a lot of reflection.

Answer 1

To answer your question. No.

• Generics gives you "algorithm reuse" - you write code independent of a data Type. the dynamic keyword doesn't do anything related to this. I define List and then i can use it for List of strings, ints, etc...
• Type safety: The whole compile time checking debate. Dynamic variables will not alert you with compile time warnings/errors in case you make a mistake they will just blow up at runtime if the method you attempt to invoke is missing. Static vs Dynamic typing debate
• Performance : Generics improves the performance for algorithms/code using Value types by a significant order of magnitude. It prevents the whole boxing-unboxing cycle that cost us pre-Generics. Dynamic doesn't do anything for this too.

What the dynamic keyword would give you is

• simpler code (when you are interoperating with Excel lets say..) You don't need to specify the name of the classes or the object model. If you invoke the right methods, the runtime will take care of invoking that method if it exists in the object at that time. The compiler lets you get away even if the method is not defined. However it implies that this will be slower than making a compiler-verified/static-typed method call since the CLR would have to perform checks before making a dynamic var field/method invoke.
• The dynamic variable can hold different types of objects at different points of time - You're not bound to a specific family or type of objects.