On 22/11/16 16:59 +0200, Ville Voutilainen wrote:
On 22 November 2016 at 15:36, Jonathan Wakely <jwak...@redhat.com> wrote:
+#if __cplusplus > 201402L || !defined(__STRICT_ANSI__) // c++1z or
gnu++11
+ template<typename _T1, typename _T2>
+ inline
+ typename enable_if<__not_<__and_<__is_swappable<_T1>,
+ __is_swappable<_T2>>>::value>::type
+ swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
Is there any advantage to using __not_ here, rather than just:
typename enable_if<!__and_<__is_swappable<_T1>,
__is_swappable<_T2>>::value>::type
?
__not_ is useful as a sub-expression of an __and_ / __or_ expression,
but at the top level doesn't seem to buy anything, and is more typing,
and requires indenting the code further.
There's no particular advantage, it's just a habitual way to write a mixture of
__and_s and __not_s that I suffer from, whichever way the nesting is.
I'm also not consistent:
+ inline enable_if_t<!(is_move_constructible_v<_Tp> && is_swappable_v<_Tp>)>
+ swap(optional<_Tp>&, optional<_Tp>&) = delete;
Yes, I noticed that :-)
so I can certainly change all these swaps to use operator! rather than
__not_. Is the
patch otherwise ok for trunk? What about the tuple part?
Yes, OK changing the top-level __not_s to operator!
I haven't reviewed the tuple part fully yet.
