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Re: Curried <functional> function objects

From: Arthur O'Dwyer <arthur.j.odwyer_at_[hidden]>
Date: Tue, 14 Apr 2020 21:10:54 -0400
On Tue, Apr 14, 2020 at 8:41 PM Justin Bassett via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> I use the function objects in <functional> all the time in conjunction
> with algorithms. However, sometimes, I find that I really want a curried
> function. For example:
>
> find_if(b, e, not_equal_to(0));
> transform(b, e, plus(1));
> copy_if(b, e, o, less(0))
>

In C++14, you can say

    auto plus1 = [](auto x) { return x + 1; };
    std::transform(b, e, dest, plus1);

or even

    auto plus = [](auto x) { return [x](auto y) { return x + y; }; };
    std::transform(b, e, dest, plus(1));

if the parameter absolutely *must* be substituted in at run time.

Do these not fit your needs for production code? If not, why not?

–Arthur

Received on 2020-04-14 20:14:01