std::tuple_cat
| Defined in header <tuple>
|
||
| template< class... Tuples > std::tuple<CTypes...> tuple_cat(Tuples&&... args); |
(since C++11) (constexpr since C++14) |
|
Constructs a tuple that is a concatenation of all tuples in args.
Parameters
| args | - | zero or more tuples to concatenate |
Return value
A std::tuple object composed of all elements of all argument tuples constructed from std::get<i>(std::forward<Ti>(arg)) for each individual element.
Example
Run this code
#include <iostream> #include <tuple> #include <string> // helper function to print a tuple of any size template<class Tuple, std::size_t N> struct TuplePrinter { static void print(const Tuple& t) { TuplePrinter<Tuple, N-1>::print(t); std::cout << ", " << std::get<N-1>(t); } }; template<class Tuple> struct TuplePrinter<Tuple, 1> { static void print(const Tuple& t) { std::cout << std::get<0>(t); } }; template<class... Args> void print(const std::tuple<Args...>& t) { std::cout << "("; TuplePrinter<decltype(t), sizeof...(Args)>::print(t); std::cout << ")\n"; } // end helper function int main() { std::tuple<int, std::string, float> t1(10, "Test", 3.14); int n = 7; auto t2 = std::tuple_cat(t1, std::make_pair("Foo", "bar"), t1, std::tie(n)); n = 10; print(t2); }
Output:
(10, Test, 3.14, Foo, bar, 10, Test, 3.14, 10)
See also
creates a tuple object of the type defined by the argument types (function template) | |
creates a tuple of lvalue references or unpacks a tuple into individual objects (function template) | |
creates a tuple of rvalue references (function template) |