Constant References

Thu Nov 13, 2008 2:17 pm

cpp code

#include <iostream>

using namespace std;

// This simply sets a to a function of b.
void fred(int &a, const int &b)
{
        a = 2 * b * b;

        // This would be illegal:
        //   b = 10;
}

main()
{
        int m;

        fred(m, 17);
        cout << "m = " << m << endl;

        int c = 45;
        fred(m, 2*c + m);
        cout << "m = " << m << endl;
}

The const modifier on a reference parameter means that the function will not change the item referred to.

Note that it is allowed to pass an expression parameter to a const reference, since it will not be assigned.

We'll find more use for this feature later, when we start flinging around things larger than integers and floats.

Constant References

Constant References

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