std::basic_string::operator[]
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                    |   reference       operator[]( size_type pos );  | 
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|   const_reference operator[]( size_type pos ) const;  | 
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Returns a reference to the character at specified location pos. No bounds checking is performed.
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 1) If pos == size(), the behavior is undefined. 
2) If pos == size(), a reference to the character with value CharT() (the null character) is returned. 
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(until C++11) | 
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 If pos == size(), a reference to the character with value CharT() (the null character) is returned. For the first (non-const) version,the behavior is undefined if this character is modified.  | 
(since C++11) | 
Contents | 
[edit] Parameters
| pos | - | position of the character to return | 
[edit] Return value
Reference to the requested character.
[edit] Complexity
Constant.
[edit] See also
|     access specified character with bounds checking  (public member function)  | |