On Saturday, 11 November 2017 at 05:20:39 UTC, codephantom wrote:
I just saw this about the new 'damnit' operator, for C# 8.
https://github.com/dotnet/csharplang/issues/556
The principle is a good one - by default you cannot dereference
something that can be null, you get a compiler error instead. If
you are confident it isn't null, you use a special operator to
override the compiler check. This is better because:
1. The programmer has to acknowledge that the reference is
nullable (except where the compiler may be able to prove it is
not null).
2. People reading the code are informed that potentially the
reference is null but the programmer thought it wouldn't be, in
this particular case, documenting the programmer's understanding.
3. Reviewers are freed from checking r's possible assigned value
in all code paths every time r is dereferenced.
This solution is probably less disruptive to existing code than
removing null altogether like Rust, which encourages the
programmer to always handle the not-null and null case for every
dereference. (Although half the battle is having non-null types).
