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Re: [std-proposals] [Resurrected Proposal] Concept introduces a typename

From: Andrew Tomazos <andrewtomazos_at_[hidden]>
Date: Wed, 3 May 2023 02:13:48 +1000
Regardless of the polls, politics or history: I think the underlying
design principle should be that: a type, a concept and auto should be
interchangeable. All three are sets of types. A type represents the set
of types of size one that includes only that type. A concept represents
the set of all types that conform to the concepts requirements. auto
represents the set of all types (aka the anything concept or the wildcard
concept). All three should be able to appear syntactically wherever one
can appear, and to mean "one of the types of this set of types". The
implications of that should be secondary.

On Wed, May 3, 2023 at 1:42 AM Barry Revzin via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On Tue, May 2, 2023, 8:05 AM Ville Voutilainen via Std-Proposals <
> std-proposals_at_[hidden]> wrote:
>> On Tue, 2 May 2023 at 14:32, Andrew Tomazos via Std-Proposals
>> <std-proposals_at_[hidden]> wrote:
>> > They added this auto nonsense at the last minute
>> The slight problem with that claim is that it's incorrect; the
>> constrained-deduced syntax wasn't added at the last minute.
>> The other problem is that while you're entitled to calling whatever
>> you like nonsense, there are significant technical
>> advantages to the approach we ended up choosing (Nota Bene: this "we"
>> excludes the author of the email I'm responding
>> to, as he wasn't a participant in any of it, so feel free to take his
>> reports on what happened and why with a modicum
>> of suspicion, as it's not based on first-hand experience), so there
>> are plausible reasons to think that it's far from nonsense.
> +1
>> > Most think that's silly and not worth fouling up the syntax
>> The slight problem with this claim is that it has no evidence backing it.
> +1.
> For instance, in Jacksonville there was a poll for the Concepts TS syntax
> with independent binding - that is: void f(Concept, Concept) can take two
> different types. That poll was 23-15-26.
> There was another poll for independent binding plus some unspecified
> syntax indicating that the function is a template. That result was 40-16-11.
> Hard to interpret that as "most think it's silly."
> Barry
>> --
> Std-Proposals mailing list
> Std-Proposals_at_[hidden]
> https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals

Received on 2023-05-02 16:14:01