std::basic_string_view::at
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                    < cpp | string | basic string view
                    
                                                            
                    | constexpr const_reference at(size_type pos) const; | (since C++17) | |
Returns a reference to the character at specified location pos. Bounds checking is performed, exception of type std::out_of_range will be thrown on invalid access.
| Contents | 
[edit] Parameters
| pos | - | position of the character to return | 
[edit] Return value
Reference to the requested character.
[edit] Exceptions
Throws std::out_of_range if pos >= size().
[edit] Complexity
Constant.
[edit] See also
| access specified character (public member function) |