22 General utilities library [utilities]

22.4 Tuples [tuple]

22.4.9 Tuple traits [tuple.traits]

template<class... Types, class Alloc> struct uses_allocator<tuple<Types...>, Alloc> : true_type { };
Preconditions: Alloc meets the Cpp17Allocator requirements ([allocator.requirements.general]).
[Note 1:
Specialization of this trait informs other library components that tuple can be constructed with an allocator, even though it does not have a nested allocator_­type.
— end note]