nction
    signature or a strict symmetric behaviour, you should set
    <code>BOOST_FORCE_SYMMETRIC_OPERATORS</code> in your user-config. This
    will force the NRVO-friendly implementation to be used even for compilers
    that don't implement the NRVO. <br>
     <br>

    <h3><a name="grpd_oprs">Grouped Arithmetic Operators</a></h3>

    <p>The following templates provide common groups of related operations.
    For example, since a type which is addable is usually also subractable,
    the <code><a hre