std::tuple_size(std::span)
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                    |   Defined in header  <span>
  | 
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|   template< class T, std::size_t N > class tuple_size< std::span<T, N> > :  | 
(1) | (since C++20) | 
|   template< class T > class tuple_size< std::span<T, std::dynamic_extent> >; // Not defined  | 
(2) | (since C++20) | 
Provides access to the number of elements in a static-extent span as a compile-time constant expression. If the span has dynamic extent, the tuple_size specialization is an incomplete type.
Inherited from std::integral_constant
Member constants
|    value [static]  | 
   N, the number of elements in the span  (public static member constant)  | 
Member functions
|    operator std::size_t  | 
   converts the object to std::size_t, returns value  (public member function)  | 
|    operator() (C++14)  | 
   returns value  (public member function)  | 
Member types
| Type | Definition | 
  value_type
 | 
  std::size_t
 | 
  type
 | 
std::integral_constant<std::size_t, value> | 
Example
| This section is incomplete Reason: no example  | 
See also
   obtains the size of tuple at compile time  (class template specialization)  |