[RFC] Throwing an exception with null pointers

[Steven Schveighoffer]

On Monday, 14 April 2025 at 15:42:07 UTC, Derek Fawcus wrote:
> On Monday, 14 April 2025 at 15:24:37 UTC, Richard (Rikki) 
> Andrew Cattermole wrote:
>>
>> It is important to note that a task isn't always a process. 
>> But once an event like null dereference occurs that task must 
>> die.
>
> It is not the dereference which is the issue, that is the 
> downstream symptom of an earlier problem.  If that reference is 
> never supposed to be null, then the program is already in a non 
> deterministic even without the crash.

This is the exact problem. The solution proposed here just 
doesn't understand what the actual problem is. Null dereferences, 
and index out-of-bounds are *programming errors*. You need to fix 
them in the program, not recover and hope for the best.

Trying to recover is the equivalent of a compiler resolving a 
syntax ambiguity with a random number generator.

Null dereference?
1. Is it because I trusted a user value? => validate user input, 
rebuild, redeploy
2. Is it because I forgot to initialize something? => initialize 
it, rebuild, redeploy
3. Is it because I forgot to validate something? => do the 
validation properly, fix whatever it was sending in invalid data, 
rebuild, redeploy
4. Is it something else? => thank you program, for crashing 
instead of corrupting everything. Now, time to find the memory 
corruption somewhere.

Similar flow chart for out-of-bounds errors.

-Steve