is_always_equal

template<typename _Alloc>

using std::allocator_traits< _Alloc >::is_always_equal = typename __detected_or_t<is_empty<_Alloc>, __equal, _Alloc>::type

Whether all instances of the allocator type compare equal.

Alloc::is_always_equal if that type exists, otherwise is_empty<Alloc>::type

Definition at line 365 of file bits/alloc_traits.h.