On Saturday, 16 August 2025 at 22:28:15 UTC, Andy Valencia wrote:
On Saturday, 16 August 2025 at 21:58:30 UTC, Paul Backus wrote:
Creating a pointer that points out-of-bounds does not, by
itself, result in undefined behavior.
However, such a pointer would not be considered a [safe
value][1], because dereferencing it *would* result in
undefined behavior.
I'm just pondering whether the intention was to accomodate this
looping pattern:
```d
int sum_values(int* p, uint nval) {
int result = 0;
foreach(_; 0 .. nval) {
result += *p++;
}
return result;
}
```
A C idiom (I've so very much embraced not using pointers in my
D world) which technically leaves "p" pointing beyond the
memory range. Perhaps this is the special case being addressed?
Andy
c++ iterators had to *start* as backwards compadable with plain
pointers (steponov was a no body before stl, and even if the
standards care about him now, they wouldntve before he published)
this was terrible, that api is ugly
Iterators are two pointers and one is 1 off the end of the
array(presumably so you could make the ugly for statement work);
I think its a little culty to claim the "c's biggest mistake" but
as an api, yes its better in ranges
d is c++ replacement, and ranges are about cleaning up iterator,
d2 and ranges was 10-ish years ago, programming in d is also
10-ish years ago
