[cfe-dev] Help getting started

[Richard Smith]

On Thu, January 5, 2012 02:01, Dave Abrahams wrote:
> on Wed Jan 04 2012, "Richard Smith"
> <richard-Qo5EllUWu/sqdlJmJB21zg-AT-public.gmane.org> wrote:
>> I'd be somewhat wary of overloading the meaning of 'auto' in this way.
>> Another
>> likely proposal for 'auto' extension is allowing 'auto' anywhere within a
>> variable's type, and deducing the appropriate type from the initializer.
>> Hence:
>>
>>
>> auto (&min)(auto x, auto y) = std::min<int>;
>
> [FYI, that code is technically nonportable because you can't know
> whether std::min has additional, defaulted arguments. ;-) ]

That provision only applies to member functions; see 17.6.5.4/3 for the
non-member case :)

>> Perhaps 'template' would be a better keyword to propose than 'auto' here?
>>
>> auto min(template a, template b) -> std::remove_reference<decltype(a < b ?
>> a : b)> noexcept(noexcept(a < b ? a : b)) { return a < b ? a : b; }
>>
>> ... or more tersely ...
>>
>> auto min(template a, template b) noexcept(auto) { return a < b ? a : b; }
>
> No offense, but that is way too far from what I am trying to accomplish
> to be of much interest to me.  I'm sticking with
>
> []min(a, b) { return a < b ? a : b; }

I wasn't intending to suggest you do any differently -- I was commenting on
the proposal to use 'auto' as a parameter type for creating an implicit
template, not your proposal (which I quite like).

- Richard