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Re: [std-proposals] On the standardization of mp-units P3045R1

From: Mateusz Pusz <mateusz.pusz_at_[hidden]>
Date: Tue, 18 Jun 2024 17:43:55 +0200
BTW, as of today, we do not provide text output for quantity points:
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p3045r1.html#quantity-point-text-output
.

In case anyone has some ideas on how we can improve here, please let us
know.

wt., 18 cze 2024 o 17:38 Mateusz Pusz <mateusz.pusz_at_[hidden]> napisał(a):

> Multiply syntax will always create a quantity. So if I write:
>
> auto q = 4 * deg_C;
>
> I will end up with a delta temperature equal to 4 K.
>
> quantity q = 4 * deg_C; // the same thing as above
>
> If I try:
>
> quantity_point qp = 4 * deg_C;
>
> I will get a compile-time error as a quantity_point is not implicitly
> constructible from the quantity.
>
> To create a quantity_point, I have to do one of the following:
>
> quantity_point qp1 = zeroth_degree_Celsius + 4 * deg_C;
> quantity_point qp2(4 * deg_C, zeroth_degree_Celsius);
> quantity_point qp3(4 * deg_C); // proper point origin provided by default
>
> All of the above will create a temperature point with a value equal
> to 277.15 K.
>
> wt., 18 cze 2024 o 17:31 Gašper Ažman via Std-Proposals <
> std-proposals_at_[hidden]> napisał(a):
>
>> it's 28 delta-K.
>>
>> On Tue, Jun 18, 2024 at 4:30 PM Ville Voutilainen via Std-Proposals
>> <std-proposals_at_[hidden]> wrote:
>> >
>> > On Tue, 18 Jun 2024 at 15:28, Tiago Freire via Std-Proposals
>> > <std-proposals_at_[hidden]> wrote:
>> > > quantity Temperature = (28.0 * deg_C).in(K);
>> >
>> > Okay people, let's backtrack a bit. Is that temperature 28K?
>> > --
>> > Std-Proposals mailing list
>> > Std-Proposals_at_[hidden]
>> > https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals
>> --
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>>
>

Received on 2024-06-18 15:44:10