public delegate Task DuplexStreamingServerMethod<TRequest, TResponse>(
	IAsyncStreamReader<TRequest> requestStream,
	IServerStreamWriter<TResponse> responseStream,
	ServerCallContext context
)
where TRequest : class
where TResponse : class

Public Delegate Function DuplexStreamingServerMethod(Of TRequest As Class, TResponse As Class) ( 
	requestStream As IAsyncStreamReader(Of TRequest),
	responseStream As IServerStreamWriter(Of TResponse),
	context As ServerCallContext
) As Task

generic<typename TRequest, typename TResponse>
where TRequest : ref class
where TResponse : ref class
public delegate Task^ DuplexStreamingServerMethod(
	IAsyncStreamReader<TRequest>^ requestStream, 
	IServerStreamWriter<TResponse>^ responseStream, 
	ServerCallContext^ context
)

type DuplexStreamingServerMethod = 
    delegate of 
        requestStream : IAsyncStreamReader<'TRequest> * 
        responseStream : IServerStreamWriter<'TResponse> * 
        context : ServerCallContext -> Task