What is the rationale behind enabling Nullable!T to be used as a regular T?

[FeepingCreature]

On Friday, 14 February 2020 at 08:54:41 UTC, Adnan wrote:
> What is the rationale behind enabling Nullable!T to be used as 
> a regular T?

The rationale is we have a few more months to wait before the 
deprecation period for that functionality runs out and we can 
remove it. :)

> Back to D.
>
> const Nullable!int a;
> assert(a.isNull);
> writeln(a + 4); // compiles with 0 warnings
>
> Why is opBinary implemented for Nullable!T? Doesn't it defeat 
> its purpose?

If you switch to 2.090.1, you will get warnings there. If you run 
with -de, the warnings will be errors.

---

The original reason was I believe that Nullable was never really 
intended to be Optional, it was intended to give types a "null" 
state like objects and pointers. Well, objects and pointers crash 
when you access them if they're null, so...

(No, it's not a very good reason.)