std::experimental::ranges::CopyConstructible
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                    < cpp | experimental | ranges
                    
                                                            
                    | Defined in header  <experimental/ranges/concepts> | ||
| template <class T> concept bool CopyConstructible = | (ranges TS) | |
The concept CopyConstructible is satisfied if T is an lvalue reference type, or if it is a MoveConstructible object type where an object of that type can constructed from a (possibly const) lvalue or const rvalue of that type in both direct- and copy-initialization contexts with the usual semantics (a copy is constructed with the source unchanged).
More precisely, if T is an object type, then CopyConstructible<T> is satisfied only if given
-  v, a lvalue of type (possibly const)Tor an rvalue of type const T,
the following are true:
-  After the definition T u = v;, uis equal tov;
-  T{v}is equal tov.
See also
| (C++11)(C++11)(C++11) | checks if a type has a copy constructor (class template) |