deduction guides for std::tuple
From cppreference.com
Defined in header <tuple> | ||
template<class... UTypes> tuple(UTypes...)-> tuple<UTypes...>; | (1) | (since C++17) |
template<class T1, class T2> tuple(std::pair<T1, T2>)-> tuple<T1, T2>; | (2) | (since C++17) |
template<class Alloc, class... UTypes> tuple(std::allocator_arg_t, Alloc, UTypes...)-> tuple<UTypes...>; | (3) | (since C++17) |
template<class Alloc, class T1, class T2> tuple(std::allocator_arg_t, Alloc, std::pair<T1, T2>)-> tuple<T1, T2>; | (4) | (since C++17) |
template<class Alloc, class... UTypes> tuple(std::allocator_arg_t, Alloc, tuple<UTypes...>)-> tuple<UTypes...>; | (5) | (since C++17) |
These deduction guides are provided for std::tuple to account for the edge cases missed by the implicit deduction guides, in particular, non-copyable arguments and array to pointer conversion.
[edit]Example
Run this code
#include <tuple>int main(){int a[2], b[3], c[4];std::tuple t1{a, b, c};// explicit deduction guide is used in this case}