is equivalent to:

<pre>
for (size_type i = 0; i != this-&gt;size(); ++i)
  (*this)[i] = (*this)[i] | rhs[i];
</pre>

<b>Returns:</b> <tt>*this</tt>.<br />
 <b>Throws:</b> nothing.

<hr />
<pre>
dynamic_bitset&amp; <a id=
"op-xor-assign">operator^=</a>(const dynamic_bitset&amp; rhs)
</pre>

<b>Requires:</b> <tt>this-&gt;size() == rhs.size()</tt>.<br />
 <b>Effects:</b> Bitwise-XOR's all the bits in <tt>rhs</tt> with
the bits in this bitset. This is equivalent to:

<pre>
for (size_type i = 0; i != this-&gt;s