Opt-in non-null class references?

[Chris M.]

On Wednesday, 28 February 2018 at 13:43:37 UTC, SimonN wrote:
> Hi,
>
> Andrei said in 2014 that not-null-references should be the 
> priority of 2014's language design, with consideration to make 
> not-null the default. In case the code breakage is too high, 
> this can be an opt-in compiler flag.
>
> [...]

I've slowly come around to supporting this idea. I'd rather avoid 
segfaults in the first place and avoid extra effort checking for 
null if possible.

It also sets clearer expectations for a user. For example, D now:

Class func(T param); // user always needs to worry about if the 
return value is null or not, there may be that edge case where it 
is null

D with non-nullable references:

Class func(T param); // user knows that the return value will not 
be null, no need to check
Nullable!Class func(T param); // user knows they need to check 
for null and handle it.

That's my two cents anyways