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Re: [SG7] sg7 varid proposal

From: Ville Voutilainen <ville.voutilainen_at_[hidden]>
Date: Mon, 21 Dec 2020 21:38:04 +0200
On Sun, 20 Dec 2020 at 20:47, Dominic Jones via SG7
<sg7_at_[hidden]> wrote:
> Hello,
> I was wondering if I may submit a language proposal to the SG7 mailing list, please? I have never been involving in library or language proposals (or in any way with ISO C++), so I am not so sure this is the way to go about things.
> I have read the documentation on https://isocpp.org/std/submit-a-proposal , but I have not attended a committee meeting. If this requirement presently stands, may I find out how to attend the next meeting, please?

Well, howdy, welcome.

If you're in UK, perhaps Roger Orr (cc:ed) could help with the
mechanics of attendance? Study group attendance
doesn't require the full mechanics, though - study groups can have any
interested experts attend.

Some questions (not criticisms, just questions) about the proposal:

1) I'm still a bit baffled how this would be used, I mean in code. Do
you have any more concrete examples of where this
facility is important to have?

2) I would remotely-vaguely think that it might be possible to get
this information via the reflection of a variable. If you
have that reflection, you can check the name and the scope of a
variable - if those are the same, you have the same
variable. I don't know whether our proposed reflection APIs have any
particular "reflects the same entity" mechanism,
but perhaps that would be worth looking at or thinking about. Having
the identifier be a top-level API function is.. ..a
bit puzzling to me, because I wouldn't expect this to be all _that_
common use of compile-time information?

One of the reasons I ruminate about (2) is that I don't fully grasp
(1). If all you need is equality, that may be already
doable, or can easily fit into the existing APIs. If you have more
needs for the id than just (in)equality with other entities,
then the picture may change. May. May not.

Received on 2020-12-21 13:38:17