std::experimental::ranges::DefaultConstructible
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                    < cpp | experimental | ranges
                    
                                                            
                    | Defined in header  <experimental/ranges/concepts> | ||
| template < class T > concept bool DefaultConstructible = Constructible<T>; | (ranges TS) | |
The DefaultConstructible concept provides a shorthand for the common case when the question is whether a type can be constructed with no arguments.
See also
| specifies that a variable of the type can be constructed from or bound to a set of argument types (concept) | |
| checks if a type has a default constructor (class template) |