std::experimental::basic_string_view::max_size
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                    < cpp | experimental | basic string view
                    
                                                            
                    | constexpr size_type max_size() const; | (library fundamentals TS) | |
The largest possible number of char-like objects that can be referred to by a basic_string_view.
Parameters
(none)
Return value
Maximum number of characters.
Exceptions
noexcept specification:  
noexcept
  Complexity
Constant.
See also
| returns the number of characters (public member function) | |
| checks whether the view is empty (public member function) |