Question

The title basically spells it out. What interfaces have you written that makes you proud and you use a lot. I guess the guys that wrote IEnumerable<T> and not least IQueryable<T> had a good feeling after creating those.

Answer 1

I’m pleased with the design of the interface at the heart of Push LINQ. It’s a very simple interface, but with it you can do all kinds of interesting things. Here’s the definition (from memory, but it’ll be pretty close at least):

public interface IDataProducer<T> {     event Action<T> DataProduced;     event Action EndOfData; } 

Basically it allows observers to ‘listen’ on a stream of data instead of ‘pulling’ from it in the way that IEnumerable works.

Three points of interest:

• The name sucks. I want to rename it, and I’ve had some good feedback, but the name isn’t there yet.
• The event handlers don’t follow the standard .NET conventions of having a sender/event args. In this case it really doesn’t make much sense to do so.
• The multicast nature of events makes this perfect for calculating multiple aggregates etc. All that comes for free.