rval arithmetic. The
        <code class="computeroutput">constexpr</code> facility of C++14 permits the range of the
        result to be calculated at compile time. Interval arithmetic is
        implemented in the header file "<a href="../../include/boost/safe_numerics/interval.hpp" target="_top">interval.hpp</a>".
        The range of the result is also represented as a pair of values of the
        type <a class="link" href="checked_result.html" title="checked_result&lt;R&gt;"><code class="computeroutp