std::make_from_tuple
From cppreference.com
| Defined in header <tuple>
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| template <class T, class Tuple> constexpr T make_from_tuple(Tuple&& t); |
(since C++17) | |
Construct an object of type T, using the elements of the tuple t as the arguments to the constructor.
Parameters
| t | - | tuple whose elements to be used as arguments to the constructor of T
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Return value
The constructed T object.
Notes
The tuple need not be std::tuple, and instead may be anything that supports std::get and std::tuple_size; in particular, std::array and std::pair may be used.
Due to guaranteed copy elision, T need not be movable.
Possible implementation
namespace detail { template <class T, class Tuple, std::size_t... I> constexpr T make_from_tuple_impl( Tuple&& t, std::index_sequence<I...> ) { return T(std::get<I>(std::forward<Tuple>(t))...); } } // namespace detail template <class T, class Tuple> constexpr T make_from_tuple( Tuple&& t ) { return detail::make_from_tuple_impl<T>(std::forward<Tuple>(t), std::make_index_sequence<std::tuple_size_v<std::decay_t<Tuple>>>{}); } |
Example
| This section is incomplete Reason: no example |
See also
creates a tuple object of the type defined by the argument types (function template) | |
creates a tuple of rvalue references (function template) | |
| (C++17) |
calls a function with a tuple of arguments (function template) |