[tuple.traits]

# 22 General utilities library [[utilities]](./#utilities)

## 22.4 Tuples [[tuple]](tuple#traits)

### 22.4.11 Tuple traits [tuple.traits]

[🔗](#lib:uses_allocator%3ctuple%3e)

`template<class... Types, class Alloc>
  struct uses_allocator<tuple<Types...>, Alloc> : true_type { };
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L3118)

*Preconditions*: Alloc meets
the [*Cpp17Allocator*](allocator.requirements.general#:Cpp17Allocator "16.4.4.6.1 General [allocator.requirements.general]") requirements ([[allocator.requirements.general]](allocator.requirements.general "16.4.4.6.1 General"))[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/utilities.tex#L3123)

[*Note [1](#note-1)*:

Specialization of this trait informs other library components thattuple can be constructed with an allocator, even though it does not have
a nested allocator_type[.](#2.sentence-1)

— *end note*]