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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. |
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| 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. |
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| <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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| 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 Marcin Kalicinski<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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