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Re: On "transparently replaceable" in std::vector operations

From: Christopher Hallock <christopherhallock_at_[hidden]>
Date: Wed, 28 Apr 2021 10:34:44 -0400
On Tue, Apr 27, 2021 at 11:02 AM Giuseppe D'Angelo via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> [vector.modifiers] says that inserting an element at position `p`
> invalidates all iterators, references and pointers from position `p`
> onwards.
> I'm wondering why there's such a requirement for pointers (and
> references) [...]

This kind of Library provision, saying that iterators, pointers, and
references to elements are invalidated upon condition X, seems overly broad
even if you don't care about using pointers in an "index-like" way, because
it means you can't safely use an element type that stores (and properly
updates across moves/copies) the 'this' pointer as a member. I suspect that
the real intent of this kind of provision is that it only applies to
iterators, pointers, and references obtained through the container's API.

Received on 2021-04-28 09:35:07