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std::add_lvalue_reference, std::add_rvalue_reference

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add_lvalue_referenceadd_rvalue_reference
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Defined in header <type_traits>
template< class T >
struct add_lvalue_reference;
 (1) (since C++11)
template< class T >
struct add_rvalue_reference;
 (2) (since C++11)

Creates an lvalue or rvalue reference type of T.

 Type trait  The type referred by the nested type type
 T is a referenceable type   T is not a referenceable type 
(1) T&[1] T
(2) T&&[2]
  1. ↑ This rule reflects the semantics of reference collapsing.
  2. ↑ This rule reflects the semantics of reference collapsing. Note that std::add_rvalue_reference<T&>::type is T&, which is not an rvalue reference type.

If the program adds specializations for any of the templates described on this page, the behavior is undefined.

Contents

[edit] Nested types

Name Definition
type determined as above

[edit] Helper types

template< class T >
using add_lvalue_reference_t = typename add_lvalue_reference<T>::type;
 (since C++14)
template< class T >
using add_rvalue_reference_t = typename add_rvalue_reference<T>::type;
 (since C++14)

[edit] Notes

The major difference to directly using T& or T&& is that T can be a non-