std::experimental::basic_string_view::copy
From cppreference.com
                    
                                        
                    < cpp | experimental | basic string view
                    
                                                            
                    | size_type copy( CharT* dest,                 size_type count, | (library fundamentals TS) | |
Copies the substring [pos, pos + rcount) to the character string pointed to by dest, where rcount is the smaller of count and size() - pos.
| Contents | 
[edit] Parameters
| dest | - | pointer to the destination character string | 
| pos | - | position of the first character | 
| count | - | requested substring length | 
[edit] Return value
Number of characters copied
[edit] Exceptions
std::out_of_range if pos >= size().
[edit] Complexity
Linear in rcount.
[edit] See also
| returns a substring (public member function) |