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Re: [std-proposals] Add operator for element wise multiplication.

From: Gašper Ažman <gasper.azman_at_[hidden]>
Date: Mon, 16 May 2022 11:45:14 +0100
... and I forgot the `hadamard` before the final semicolon to actually
define the variable for the operator.

On Mon, May 16, 2022 at 11:44 AM Gašper Ažman <gasper.azman_at_[hidden]>
wrote:

> You know you can spell it as
> x *hadamard* y
> by defining
> static constexpr hadamard_t final {
> struct hadamard_proxy_t {
> matrix const* m;
> friend auto operator*(hadamard_proxy_t const& self, matrix const&
> y) -> matrix {
> return hadamard_product(*self.m, y);
> }
> };
> friend auto operator*(matrix const& x, hadamard_t) -> hadamard_proxy_t
> {
> return hadamard_proxy_t{&x};
> }
> };
>
> I omitted the associativity helpers which are symmetric for brevity, and
> of course I completely neglected all the lvalue/rvalue forwarders, but it's
> close enough to give a hint.
>
> G
>
> On Mon, May 16, 2022 at 9:58 AM Patrik Tegelberg via Std-Proposals <
> std-proposals_at_[hidden]> wrote:
>
>> P.S. about overloading operator ->*.
>>
>> Come to think of it, the dot product can not use *= so I’ll let * mean
>> point wise, which do use **= and let ->** mean dot product, so ->*= is
>> never needed.
>>
>>
>>
>> Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for
>> Windows
>>
>>
>>
>> *From: *Sebastian Wittmeier via Std-Proposals
>> <std-proposals_at_[hidden]>
>> *Sent: *Sunday, 15 May 2022 22:08
>> *To: *std-proposals_at_[hidden]
>> *Cc: *Sebastian Wittmeier <wittmeier_at_[hidden]>
>> *Subject: *Re: [std-proposals] Add operator for element wise
>> multiplication.
>>
>>
>>
>> Hi Patrik,
>>
>> operator->* (pointer-to-member) can be overridden and is very similar in
>> precedence to multiplication (one step higher only).
>>
>> Best,
>>
>> Sebastian
>>
>> --
>>
>> Sebastian Wittmeier
>>
>>
>> --
>> Std-Proposals mailing list
>> Std-Proposals_at_[hidden]
>> https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals
>>
>

Received on 2022-05-16 10:45:26