t
</pre>

<b>Requires:</b> <tt>this-&gt;size() == a.size()</tt><br />
<b>Returns:</b> true if this bitset is a subset of bitset
<tt>a</tt>. That is, it returns true if, for every bit that is
set in this bitset, the corresponding bit in bitset <tt>a</tt> is
also set. Otherwise this function returns false.<br />
<b>Throws:</b> nothing.

<hr />
<pre>
bool <a id=
"is_proper_subset_of">is_proper_subset_of</a>(const dynamic_bitset&amp; a) const
</pre>

<b>Requires:</b> <tt>this-&gt;size() == a.size()</tt><br />
<