ameterSpec| via ``typedef``
=============================================

In principle you can declare a |ParameterSpec| as a ``typedef``
for a specialization of ``parameters<…>``, but Microsoft Visual C++
6.x has been seen to choke on that usage.  The workaround is to use
inheritance and declare your |ParameterSpec| as a class:

.. parsed-literal::

     **struct dfs_parameters
       :** parameter::parameters<
           tag::graph, tag::visitor, tag::root_vertex
         , tag::index_map, tag::color_m