20 General utilities library [utilities]

20.5 Tuples [tuple]

20.5.9 Tuple traits [tuple.traits]

template<class... Types, class Alloc> struct uses_allocator<tuple<Types...>, Alloc> : true_type { };
Preconditions: Alloc meets the Cpp17Allocator requirements (Table 36).
[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]