David Arno

In your example, you have made `IResult` covariant. Make it contravariant and then `IResult` can be used in place of `IResult`: ```cs public interface IResult { } public sealed class...

> The never type is essentially the opposite of the object type. Oh! "*A new type that has no instances and is a **subtype** of every other type*". Got there...

@JoergWMittag, Your example shows what I'm beginning to feel is a serious flaw to this idea. ~~My first thought on how this feature could be used was for the framework...

Make your code more self-explanatory and the comments can go completely: ```cs public class Canvas { public enum Color { Grass, Ocean } public enum ColorShade { Night, Day }...

@svick, >> Make your code more self-explanatory and the comments can go completely: > That might help for this simple example. But most code isn't like that and documentation comments...

@sharwell, that makes sense. I’ll duck out in that case. :+1:

@HaloFour, @aensidhe & @Liminiens, I don't agree that this proposal is equivalent to DUs. The latter are designed to be closed sets of values, that cannot be extended. Whereas this...

@dsaf, DUs in one year (C# 9) would be way better than either of your options 😄 @aensidhe, if I declare a DU: ```fs type IntOrBool = | I of...

As I've downvoted this proposal, I feel I should explain why, even though the majority may disagree with me and downvote this... To my mind, the statement "*...there is a...

@gafter, I've started writing a draft proposal around #75. Would you like me to continue with this, or did you have a proposal planned yourself?