vector::const_reference
A type that provides read-only access to elements in a vector.
typedef typename Allocator::const_reference const_reference;
Remarks
A type const_reference cannot be used to modify the value of an element. You can use const_reference on non-const elements but you must use const_reference on const elements.
Example
// vector_const_ref.cpp
// compile with: /EHsc
#include <vector>
#include <iostream>
int main( )
{
using namespace std;
vector <int> v1;
v1.push_back( 10 );
v1.push_back( 20 );
const vector <int> v2 = v1;
const int &i = v2.front( );
const int &j = v2.back( );
cout << "The first element is " << i << endl;
cout << "The second element is " << j << endl;
// The following line would cause an error as v2 is const
// v2.push_back( 30 );
}
The first element is 10 The second element is 20
Requirements
Header: <vector>
Namespace: std