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std::basic_string::operator[]

reference       operator[]( size_type pos );
 (1) 
const_reference operator[]( size_type pos ) const;
 (2)

Returns a reference to the character at specified location pos. No bounds checking is performed.

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.
(until C++11)

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)

Parameters

pos - position of the character to return

Return value

Reference to the requested character.

Complexity

Constant.

Example

#include <iostream>
#include <string>
 
int main()
{
  {
    std::string const c("Exemplar");
    for (unsigned i = 7;i != 0; i/=2)
        std::cout << c[i];
  }
    std::cout << '\n';
  {
    std::string s("Exemplar ");
    s[s.size()-1] = 'y';
    std::cout << s;
  }
}

Output:

rmx
Exemplary

See also

 access specified character with bounds checking
(public member function)

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