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Date: Sun, 07 Jun 2015 08:50:00 -0000
Message-ID: <CAFk2RUZr1ARp92-JuARcBioPTCj5Lh-K0GsPm2oapYnYWMxK2g@mail.gmail.com>
Subject: Re: [v3 PATCH] Implement N4387 and LWG 2367
From: Ville Voutilainen <ville.voutilainen@gmail.com>
To: libstdc++@gcc.gnu.org
Cc: "gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
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On 7 June 2015 at 11:33, Ville Voutilainen <ville.voutilainen@gmail.com> wrote:
>>> You use a lot: typename enable_if<X, bool>::type=true
>>> while the current code seems to favor: class=typename enable_if<X>::type.
>>> I don't really care which one is used, but it is easier to read when the
>>> style is consistent through the library.
>> It's not a style issue. That template parameter needs to be a non-type one,
>> otherwise the overloads are ambiguous.
> ...and I think it doesn't necessarily need to be non-type, I think it can be
> made to work with a type parameter that is enable_if<X, true_type>
> and enable_if<X, false_type> for the mutually-exclusive overloads.

Except that no, it can't. It really needs to be a non-type parameter. :P