ame
  type as the distance value type.<br>

  <b>Default:</b> <tt>boost::closed_plus&lt;D&gt;</tt> with
   <tt>D=typename property_traits&lt;DistanceMap&gt;::value_type</tt><br>
</blockquote>

IN: <tt>distance_inf(D distance_infinity)</tt> 
<blockquote>
  The <tt>distance_infinity</tt> object must be the greatest value of any <tt>D</tt> object.
  That is, <tt>distance_compare(d, distance_infinity) == true</tt> for any <tt>d != distance_infinity</tt>.
  The type <tt>D</tt> is the value type of the <tt>Distan