Chap 06: Comparing objects

[Strydir]

Page 235: the line "int result = x.Name.Length.CompareTo(y.Name.Length) results in the errors "'Name may be null here. Dereference of a possibly null reference".

To fix it, you must test to make sure that Name is not null first:

if((x is not null) && (y is not null)) { if(x.Name is null) return 1; if(y.Name is null) return -1; int result = x.Name.Length.CompareTo(y.Name.Length); }

Obviously, the errors disappear if you modify the file according to the "errata" for null values for page 235, but, as printed, the text does not work. A possible VS Code version issue? Using VS Code version 1.69.1

[markjprice]

It's nothing to do with Visual Studio Code. It is a mistake in the printed book. The Person class has a Name property defined as a nullable string but that statement does not check for null. That's why the errata exists to fix that, as well as improve null handling in other ways too.

[Strydir]

Well, it's not IN the errata, so I thought that I'd bring it to your attention. If you are planning on adding it, then great. I find your response rather rude.
You're welcome for bringing it to your attention.

[markjprice]

Sorry! It was not my intention to be rude. The errata as it exists both fixes the issue and improves the code example, so there is nothing to add. That's all I meant.

[Strydir]

Well, as a user, I went to your errata page specifically to find out why that page does not work and I find absolutely NO reference to the fact that there is an error in the book. I almost pitched the book (means to throw it in the garbage) because the book is apparently wrong but there is no reference to the error. Please add a note stating that there is an error on the page so that dumb people like me don't spend so much freaking TIME trying to determine if I'M missing something!
Wow!