must be
        pointers.</li>
    <li>Both Iter1 and Iter2 must point to the same type -
        excluding <font size="2" face="Courier New">const</font>
        and <font size="2" face="Courier New">volatile</font>-qualifiers.</li>
    <li>The type pointed to by Iter1 must have a trivial
        assignment operator.</li>
</ul>

<p>By trivial assignment operator we mean that the type is either
a scalar type[3] or:</p>

<ul>
    <li>The type has no user defined assignment operator.</li>
    <li>The type doe