Defined in header <concepts> | ||
---|---|---|
template < class T > concept default_initializable = std::constructible_from<T> && requires { T{}; } && /* T t; is well-formed, see below */; | (since C++20) |
The default_initializable
concept checks whether variables of type T
can be.
T()
is well-formed); T{}
is well-formed); and T t;
is well-formed). Access checking is performed as if in a context unrelated to T. Only the validity of the immediate context of the variable initialization is considered.
template<class T> concept default_initializable = std::constructible_from<T> && requires { T{}; } && requires { ::new T; }; |
(C++20) | specifies that a variable of the type can be constructed from or bound to a set of argument types (concept) |
(C++11)(C++11)(C++11) | checks if a type has a default constructor (class template) |
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https://en.cppreference.com/w/cpp/concepts/default_initializable