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
This is an older version of Boost and was released in 2013. The current version is 1.89.0.
The TR1
Tuple interface is specified to provide uniform access to std::pair
as if it were a 2 element tuple.
tuple_size<std::pair<T1, T2> >::value
Type: An MPL Integral Constant
Value: Returns 2, the number of elements in a pair.
tuple_element<0, std::pair<T1, T2> >::type
Type: T1
Value: Returns the type of the first element of the pair
tuple_element<1, std::pair<T1, T2> >::type
Type: T2
Value: Returns thetype of the second element of the pair
template<int I, typename T1, typename T2> P& get(std::pair<T1, T2>& pr); template<int I, typename T1, typename T2> const P& get(const std::pair<T1, T2>& pr);
Type: If I
== 0
P is T1,
else if I ==
1 P
is T2 else the program is
ill-formed.
Returns: pr.first
if I ==
0 else pr.second.[*Returns:
pr.first if I
== 0
else pr.second.