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<Head>
<Title>Reference Property Map</Title>
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<H2><A NAME="sec:identity-property-map"></A>
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<PRE>
template <typename KeyType, typename ValueType>
class ref_property_map
</PRE>
This property map wraps a reference to some particular object, and
returns that reference whenever a key object is input.
<H3>Where Defined</H3>
<P>
<a href="../../../boost/property_map/property_map.hpp"><TT>boost/property_map/property_map.hpp</TT></a>
<h3>Model of</h3>
<a href="./LvaluePropertyMap.html">Lvalue Property Map</a>
<h3>Associated Types</h3>
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<tr>
<th>Type</th><th>Description</th>
</tr>
<tr>
<td><tt>
boost::property_traits<ref_property_map>::value_type
</tt></td>
<td>
This type is the <tt>ValueType</tt> with which the template was instantiated.
</td>
</tr>
<tr>
<td><tt>
boost::property_traits<ref_property_map>::key_type
</tt></td>
<td>
This type is the <tt>KeyType</tt> with which the template was instantiated.
</td>
</tr>
<tr>
<td><tt>
boost::property_traits<ref_property_map>::category
</tt></td>
<td>
This type is <tt>boost::lvalue_property_map_tag</tt>.
</td>
</tr>
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<h3>Member Functions</h3>
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<tr>
<th>Member</th><th>Description</th>
</tr>
<tr>
<td><tt>
ref_property_map(ValueType& v)
</tt></td>
<td>
The constructor for ref_property_map is provided the reference that
the property map will return when queried.
</td>
</tr>
<tr>
<td><tt>
ref_property_map(const ref_property_map& x)
</tt></td>
<td>
Copy constructor.
</td>
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<tr>
<td><tt>
ValueType& operator[](KeyType const&) const
</tt></td>
<td>
Returns the contained reference.
</td>
</tr>
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