Will C# 8 be covered? Thanks.

It seems very unlikely to me that C# 8 will be concrete enough to be covered in detail before the book comes out. I already have a chapter including some of the features that are being discussed, and I hope to expand that coverage more in the coming months, but I don't expect that C# 8 will be covered in the 4th edition in the same way that C# 6 and C# 7 are.