Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
![[Home]](../mpl_logo.jpg){kind=logo}
is_sequence
template<
typename T
>
struct is_sequence
{
typedef unspecified type;
};
Returns an Integral Constant c such that c::value == true if and only if T is a model of Sequence.
#include "boost/mpl/is_sequence.hpp"
| Parameter | Requirement | Description |
|---|---|---|
T | A type |
| Expression | Expression type | Precondition | Semantics | Postcondition |
|---|---|---|---|---|
typedef is_sequence<T>::type c; | A model of bool Integral Constant | Equivalent to typedef not_< is_same< begin<T>::type,void_ > >::type c; |
Amortized constant time.
struct UDT {};
BOOST_STATIC_ASSERT( !is_sequence<int>::value );
BOOST_STATIC_ASSERT( !is_sequence<UDT>::value );
BOOST_STATIC_ASSERT( is_sequence< list<> >::value );
BOOST_STATIC_ASSERT( is_sequence< vector<> >::value );
Sequence, begin, end, as_sequence