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<a name="property_tree.container"></a><a class="link" href="container.html" title="Property Tree as a Container">Property Tree as a Container</a>
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<p>
Every property tree node models the ReversibleSequence concept, providing access
to its immediate children. This means that iterating over a <code class="computeroutput"><a class="link" href="../boost/property_tree/ptree.html" title="Type definition ptree">ptree</a></code>
(which is the same as its root node - every <code class="computeroutput"><a class="link" href="../boost/property_tree/ptree.html" title="Type definition ptree">ptree</a></code>
node is also the subtree it starts) iterates only a single level of the hierarchy.
There is no way to iterate over the entire tree.
</p>
<p>
It is very important to remember that the property sequence is <span class="bold"><strong>not</strong></span>
ordered by the key. It preserves the order of insertion. It closely resembles
a std::list. Fast access to children by name is provided via a separate lookup
structure. Do not attempt to use algorithms that expect an ordered sequence
(like binary_search) on a node's children.
</p>
<p>
The property tree exposes a second container-like interface, called the associative
view. Its iterator type is the nested type assoc_iterator (and its const counterpart
const_assoc_iterator). You can get an ordered view of all children by using
ordered_begin() and ordered_end().
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<p>
The associative view also provides find() and equal_range() members, which
return assoc_iterators, but otherwise have the same semantics as the members
of std::map of the same name.
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<p>
You can get a normal iterator from an assoc_iterator by using the to_iterator()
member function. Converting the other way is not possible.
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<td align="right"><div class="copyright-footer">Copyright © 2008-2010 Marcin Kalicinski<br>Copyright © 2010-2013 Sebastian
Redl<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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