23 General utilities library [utilities]

23.15 Metaprogramming and type traits [meta]

23.15.7 Transformations between types [meta.trans]

23.15.7.2 Reference modifications [meta.trans.ref]

Table 46 — Reference modifications
TemplateComments
template <class T>
struct remove_­reference;
If T has type “reference to T1” then the member typedef type names T1; otherwise, type names T.
template <class T>
struct add_­lvalue_­reference;
If T names a referenceable type then the member typedef type names T&; otherwise, type names T. [Note: This rule reflects the semantics of reference collapsing ([dcl.ref]). end note]
template <class T>
struct add_­rvalue_­reference;
If T names a referenceable type then the member typedef type names T&&; otherwise, type names T. [Note: This rule reflects the semantics of reference collapsing ([dcl.ref]). For example, when a type T names a type T1&, the type add_­rvalue_­reference_­t<T> is not an rvalue reference. end note]