class template specialization
<utility>

std::tuple_size<pair>

unspecialized
template <class Tpl> class tuple_size;
pair specialization
template <class T1, class T2>
  struct tuple_size< pair<T1,T2> >;
Tuple traits for pair
Accesses the size of a pair object as if it was a tuple.

This class provides the size of the pair (which is always 2) as the constexpr member value of type size_t, as if inheriting integral_constant:
This class provides the size of the pair (which is always 2) as the constexpr member value of type size_t by inheriting integral_constant:

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template <class Tpl> class tuple_size;
template <class T1, class T2>
  struct tuple_size< pair<T1,T2> > : integral_constant <size_t,2> {};


See tuple_size for more information.

Template parameters

Tpl
Tuple-like type. For this specialization: pair<T1,T2>.
T1, T2
Type of the elements in the pair.

Member contants

member constantdefinition
value(size_t)2
size_t is an unsigned integral type.

See also

tuple_size
Tuple size traits (class template )
tuple_element<pair>
Tuple element type for pair (class template specialization )

C++