That is called an index. If you want it to be standalone, you can bundle it with...

sparkie · 2026-08-30T23:37:04

I think parent was after base+offset+index rather than just base+index.

Examples would be eg, `string_view` or `ArraySegment`. They hold some offset relative to a base allocation, and when we index the string_view or ArraySegment we're indexing relative to that offset.

pocksuppet · 2026-09-10T17:25:23

That is called pointer arithmetic on the base

tialaramex · 2026-08-31T08:42:12

Presumably `string_view` is referring to C++ std::string_view ?

It's not holding an "offset", it's a fat pointer, (ptr,len) or possibly (start,end)

You're imagining this as (string_ptr,offset,len) but that's 50% bigger for no practical benefit, you cannot unwind a std::string_view to get the string it's a view into, indeed there may never have been such a string.

dminik · 2026-08-30T23:46:59

I wish languages made it easier (or possible) to track index ownership at compile time.

afdbcreid · 2026-08-31T01:17:39

You can in Rust! You just bundle it with a lifetime.

But... This loses the reason people are using indices to begin with: because the borrow checker cannot track what they do.