https://issues.dlang.org/show_bug.cgi?id=21397

          Issue ID: 21397
           Summary: Nullable doesn't define copy constructors
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: ilyayaroshenko@gmail.com

--