On Borrow Checking

[Derek Fawcus]

On Sunday, 18 May 2025 at 12:20:54 UTC, claptrap wrote:
> On Saturday, 17 May 2025 at 14:03:05 UTC, Richard (Rikki) 
> Andrew Cattermole wrote:
>> Any kind of pointer originating from the ``this`` pointer of a 
>> RC type,
>> must not outlive the RC owner.
>
> We have the same problem with manual memory management don't we?
> So is "safe manual memory management" considered not possible 
> in D?

Of the cases:
   1) spatial
   2) temporal
   3) type
   4) init

It is only really '2' which is problematic for safe manual 
management in D, e.g. betterC mode with @safe + dip1000 + 
dip1021.  i.e. use-after-free and double-free.

I happened to read a piece yesterday, about tagged pointers as a 
form of smart pointer for C++, and it should be directly 
convertible to D.

https://btmc.substack.com/p/tagged-pointers-for-memory-safety