std::uses_allocator<std::tuple>

 

C++

Language

Standard library headers

Concepts

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)

Dynamic memory management

Error handling

Program utilities

Variadic functions

Date and time

Function objects

initializer_list (C++11)

bitset

hash (C++11)

Relational operators

rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=

Optional and any

optional (C++17)

any (C++17)

Pairs and tuples

pair

tuple (C++11)

apply (C++17)

piecewise_construct_t (C++11)

piecewise_construct (C++11)

integer_sequence (C++14)

Swap, forward and move

swap

exchange (C++14)

forward (C++11)

move (C++11)

move_if_noexcept (C++11)

Type operations

declval (C++11)

as_const (C++17)

 

std::tuple

Member functions

tuple::tuple

tuple::operator=

tuple::swap

Non-member functions

make_tuple

tie

forward_as_tuple

tuple_cat

operator==operator!=operator<operator<=operator>operator>=

std::swap

get

Helper classes

tuple_size

tuple_element

uses_allocator

ignore

 

Defined in header <tuple>
template< class... Types, class Alloc > struct uses_allocator< std::tuple<Types...>, Alloc > : std::true_type { };		(since C++11)

This specialization of std::uses_allocator informs other library components that tuples support uses-allocator construction, even though they do not have a nested allocator_type.

Inherited from std::integral_constant

Member constants

value [static]	true (public static member constant)

Member functions

operator bool	converts the object to bool, returns value (public member function)
operator() (C++14)	returns value (public member function)

Member types

Type	Definition
value_type	bool
type	std::integral_constant<bool, value>

Example

Run this code

// myalloc is a stateful Allocator with a single-argument constructor
// that takes an int. It has no default constructor.
 
    typedef std::vector<int, myalloc<int>> innervector_t;
    typedef std::tuple<int, innervector_t> elem_t;
    typedef std::scoped_allocator_adaptor< myalloc<elem_t>, myalloc<int>> Alloc;
    Alloc a(1,2);
    std::vector<elem_t, Alloc> v(a);
    v.resize(1);                  // uses allocator #1 for elements of v
    std::get<1>(v[0]).resize(10); // uses allocator #2 for innervector_t

See also

uses_allocator (C++11)	checks if the specified type supports uses-allocator construction (class template)