Introducing Nullable Reference Types in C#. Is there hope for D, too?

[codephantom]

On Thursday, 23 November 2017 at 07:20:41 UTC, Ola Fosheim 
Grostad wrote:
> On Thursday, 23 November 2017 at 01:16:59 UTC, codephantom 
> wrote:
>> That's why we have the concept of 'undefined behaviour'.
>
> Errr, no.  High level programming languages don't have 
> undefined behaviour. That is a C concept related to the 
> performance of the executable. C tries to get as close to 
> machine language as possible.

Many high level languages let you use 'unsafe' code, where you 
can write erroneous operations - and then you're back in the 
world of undefined behaviour.

Are you saying, that a high level language can trap *all* errors?

As per the Goldbach conjecture... where is the proof?