Re: [boost] "Simple C++11 metaprogramming"

On 6/5/2015 9:42 AM, Peter Dimov wrote:

Eric Niebler wrote:

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(This implements the specification in the latest C++17 draft.)

I'm not so sure. If a user defines a specialization for common_type, it won't get used when computing common_type.

As it turns out, users are not allowed to specialize common_type, which is why the C++17 specification does not concern itself with such specializations.

Users are allowed to specialize `common_type`. There is a standing issue against SFINAE-friendly `common_type` by Eric and yours truly: https://cplusplus.github.io/LWG/lwg-active.html#2465 Regards, -- Agustín K-ballo Bergé.- http://talesofcpp.fusionfenix.com