Should (p - q) be disallowed in @safe code?

[claptrap]

On Thursday, 1 January 2026 at 06:15:09 UTC, Walter Bright wrote:
> Consider:
> ```d
> @safe
> size_t distance(int* p, int* q) => p - q;
> ```
> The difficulty here is when p and q may not be pointing into 
> the same memory object. If they're not, the result is nonsense:

I use this all the time to iterate multiple arrays in lockstep.

size_t offset = q-p;

you access q with "p[offset]", and you just iterate p

I tried to avoid using it but it is just faster sometimes,