Generic Method assigned to Delegate

c#, delegates, generics, interface, types

Solution

Your question makes no sense because you can't ever use an open generic type to declare a storage location (like a local variable or field). It must always be closed.

I understand you want to pass a `GenericDelegate<T>` to a method taking such a value as an argument. But even then the delegate type becomes closed with `T` as the generic type parameter.

In your sample code you write

someDelegate = GenericMethod;

but what type is `someDelegate` supposed to have? It must either be obviously closed (`GenericDelegate<string>`) or closed with a generic type parameter from the outer scope:

void SomeOuterMethod<T>() where T : ISomeClass {
    GenericDelegate<T> someDelegate = GenericMethod<T>;
}

I hope I understood your problem. If not, please clarify. If you elaborate a little on what you want to accomplish I'll try to suggest a practical solution.

Other languages like Haskell do have support for passing around values of open generic types (in other words, you can have a variable of type `IEnumerable<>`). This is required to implement monads. The CLR does not have that feature.

New thought: instead of a delegate you could create a non-generic base type with a generic method that can be overridden:

interface CheckHandler {
 public void Check<T>(T someArg);
}

Hope that covers your scenario. You can not freely pass any `CheckHandler` around. Its `Check` method can then be called with an arbitrary type argument.

Problem

I've been a little puzzled with Delegates and Generic Methods. Is it possible to assign a delegate to a method with a generic type parameter? I.E: ``` //This doesn't allow me to pass a generic parameter with the delegate. public delegate void GenericDelegate<T>() someDelegate = GenericMethod; public void GenericMethod<T>() where T : ISomeClass { } ``` I'm trying to pass this delegate into the function with a generic type of the interface that the method is expecting, with a function like this: ``` void CheckDelegate(GenericDelegate<ISomeClass> mechanism); ``` so that I can use the delegate like so: ``` someDelegate<ImplementsSomeClass>(); ```

Original source

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