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Coding Standards
| Front Page / Sequences / Views / single_view |
template<
typename T
>
struct single_view
{
// unspecified
// ...
};
A view onto an arbitrary type T as on a single-element sequence.
#include <boost/mpl/single_view.hpp>
| Parameter | Requirement | Description |
|---|---|---|
| T | Any type | The type to be wrapped in a sequence. |
The semantics of an expression are defined only where they differ from, or are not defined in Random Access Sequence.
In the following table, v is an instance of single_view, x is an arbitrary type.
| Expression | Semantics |
|---|---|
single_view<x> single_view<x>::type |
A single-element Random Access Sequence v such that front<v>::type is identical to x. |
| size<v>::type | The size of v; size<v>::value == 1; see Random Access Sequence. |
typedef single_view<int> view; typedef begin<view>::type first; typedef end<view>::type last; BOOST_MPL_ASSERT(( is_same< deref<first>::type,int > )); BOOST_MPL_ASSERT(( is_same< next<first>::type,last > )); BOOST_MPL_ASSERT(( is_same< prior<last>::type,first > )); BOOST_MPL_ASSERT_RELATION( size<view>::value, ==, 1 );