AspnetCore DI and contravariant fun

This line is the bane of my existence 😉 https://github.com/jbogard/MediatR/blob/master/src/MediatR/Mediator.cs#L35

Could we not do another major version bump and update IMediator.Send to be

        Task<TResponse> Send<TRequest, TResponse>(
            TRequest request,
            CancellationToken cancellationToken = default (CancellationToken))
            where TRequest : IRequest<TResponse>;

In that case we at least have some way of forcing MediatR to fetch the correct type from the container by casting it beforehand.

[jbogard]

Why not open a PR to fix that? They’re suuuuuuuper receptive about adding valuable features to core DI.

Or use a container that does support variance?

[jbogard]

Yeah, I think I’ll put this in the back burner for now. Maybe in C# 42?