C++ (and all other languages I can think of) have generally and successfully preferred simple and extensible tools for composition over a myriad of shortcuts.

Function deletion, templated or otherwise, are widely applicable tools for composition. The proposed extension of the ‘explicit’ keyword to produce the same effect as an already composable feature would be never make it past a committee.

There might be a universe where this makes it to a study group. Maybe, in a particularly strange universe, this may make it into a working group.

There is *no universe where this makes it past the committee*. This would be a redundant language feature at best.

WL

> On May 3, 2022, at 11:18 AM, Giuseppe D'Angelo via Std-Proposals <std-proposals_at_[hidden]> wrote:
>
> On 03/05/2022 16:37, Bo Persson via Std-Proposals wrote:
>> The claim was "But learning it, & understanding it takes 30 sec."
>> So maybe it takes longer (at least for me)?
>
> But learning *what* precisely? What does f(explicit X) accept?
>
> 1) only and precisely X
> 2) things implicitly convertible to X
> 3) things implicitly convertible to X without narrowing conversions
> 4) ...?
>
> Is there a concrete proposal and not something resembling my own's April Fool blog post?
>
>
> Thanks,
> --
> Giuseppe D'Angelo
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> Std-Proposals mailing list
> Std-Proposals_at_[hidden]
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