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<Head>
<Title>Boost Graph Library: Graph Traits</Title>
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<H1><A NAME=""></A>
<pre>
adjacency_list_traits&lt;EdgeList, VertexList, Directed&gt;
</pre>
</H1>

This class provides an alternate method for accessing some of the
associated types of the <tt>adjacency_list</tt> class. The main reason
for this class is that sometimes one would like to create graph
properties whose values are vertex or edge descriptors. If you try to
use <tt>graph_traits</tt> for this you will run into a problem with
mutually recursive types. To get around this problem, the
<tt>adjacency_list_traits</tt> class is provided, which gives the user
access to the vertex and edge descriptor types without requiring the
user to provide the property types for the graph.

<pre>
  template &lt;class EdgeList, class VertexList, class Directed&gt;
  struct adjacency_list_traits {
    typedef ... vertex_descriptor;
    typedef ... edge_descriptor;
    typedef ... directed_category;
    typedef ... edge_parallel_category;
  };
</pre>

<h3>Where Defined</h3>

<a href="../../../boost/graph/adjacency_list.hpp"><tt>boost/graph/adjacency_list.hpp</tt></a>

<H3>Template Parameters</H3>

<P>
<TABLE border>
<TR>
<th>Parameter</th><th>Description</th><th>Default</th>
</tr>

<TR><TD><TT>EdgeList</TT></TD>
<TD>
The selector type for the edge container implementation.
</TD>
<td><tt>vecS</tt></td>
</TR>

<TR><TD><TT>VertexList</TT></TD>
<TD>
The selector type for the vertex container implementation.
</TD>
<td><tt>vecS</tt></td>
</TR>

<TR><TD><TT>Directed</TT></TD>
<TD>
The selector type whether the graph is directed or undirected.
</TD>
<td><tt>directedS</tt></td>
</TR>

</table>

<h3>Model of</h3>

<a
href="http://www.sgi.com/tech/stl/DefaultConstructible.html">DefaultConstructible</a> and
<a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>

<h3>Type Requirements</h3>

Under construction.

<H2>Members</H2>

<p>

<table border>
<tr>
<th>Member</th><th>Description</th>
</tr>

<tr>
<td><tt>
vertex_descriptor
</tt></td>
<td>
The type for the objects used to identify vertices in the graph.
</td>
</tr>

<tr>
<td><tt>
edge_descriptor
</tt></td>
<td>
The type for the objects used to identify edges in the graph.
</td>
</tr>

<tr>
<td><tt>
directed_category
</tt></td>
<td>
This says whether the graph is undirected (<tt>undirected_tag</tt>)
or directed (<tt>directed_tag</tt>).
</td>
</tr>

<tr>
<td><tt>
edge_parallel_category
</tt></td>
<td>
This says whether the graph allows parallel edges to be inserted
(<tt>allow_parallel_edge_tag</tt>) or if it automatically removes
parallel edges (<tt>disallow_parallel_edge_tag</tt>).
</td>
</tr>

</table>

<h3>See Also</h3>

<a href="./adjacency_list.html"><tt>adjacency_list</tt></a>

<br>
<HR>
<TABLE>
<TR valign=top>
<TD nowrap>Copyright &copy; 2000-2001</TD><TD>
<A HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</A>,
Indiana University (<A
HREF="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</A>)<br>
<A HREF="http://www.boost.org/people/liequan_lee.htm">Lie-Quan Lee</A>, Indiana University (<A HREF="mailto:llee@cs.indiana.edu">llee@cs.indiana.edu</A>)<br>
<A HREF="http://www.osl.iu.edu/~lums">Andrew Lumsdaine</A>,
Indiana University (<A
HREF="mailto:lums@osl.iu.edu">lums@osl.iu.edu</A>)
</TD></TR></TABLE>

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