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diff --git a/doc/html/container/configurable_containers.html b/doc/html/container/configurable_containers.html new file mode 100644 index 0000000000..ec3b440d27 --- /dev/null +++ b/doc/html/container/configurable_containers.html @@ -0,0 +1,267 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Extended functionality: Configurable containers</title> +<link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> +<link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> +<link rel="up" href="../container.html" title="Chapter 9. Boost.Container"> +<link rel="prev" href="extended_functionality.html" title="Extended functionality: Basic extensions"> +<link rel="next" href="extended_allocators.html" title="Extended functionality: Extended allocators"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr> +<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> +<td align="center"><a href="../../../index.html">Home</a></td> +<td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> +<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> +<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="extended_functionality.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../container.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="extended_allocators.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="container.configurable_containers"></a><a class="link" href="configurable_containers.html" title="Extended functionality: Configurable containers">Extended functionality: + Configurable containers</a> +</h2></div></div></div> +<div class="toc"><dl class="toc"> +<dt><span class="section"><a href="configurable_containers.html#container.configurable_containers.configurable_tree_based_associative_containers">Configurable + tree-based associative ordered containers</a></span></dt> +<dt><span class="section"><a href="configurable_containers.html#container.configurable_containers.configurable_vectors">Configurable + vectors</a></span></dt> +</dl></div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="container.configurable_containers.configurable_tree_based_associative_containers"></a><a class="link" href="configurable_containers.html#container.configurable_containers.configurable_tree_based_associative_containers" title="Configurable tree-based associative ordered containers">Configurable + tree-based associative ordered containers</a> +</h3></div></div></div> +<p> + <code class="computeroutput"><a class="link" href="../boost/container/set.html" title="Class template set">set</a></code>, <code class="computeroutput"><a class="link" href="../boost/container/multiset.html" title="Class template multiset">multiset</a></code>, + <code class="computeroutput"><a class="link" href="../boost/container/map.html" title="Class template map">map</a></code> and <code class="computeroutput"><a class="link" href="../boost/container/multimap.html" title="Class template multimap">multimap</a></code> + associative containers are implemented as binary search trees which offer + the needed complexity and stability guarantees required by the C++ standard + for associative containers. + </p> +<p> + <span class="bold"><strong>Boost.Container</strong></span> offers the possibility to + configure at compile time some parameters of the binary search tree implementation. + This configuration is passed as the last template parameter and defined using + the utility class <code class="computeroutput"><a class="link" href="../boost/container/tree_assoc_options.html" title="Struct template tree_assoc_options">tree_assoc_options</a></code>. + The following parameters can be configured: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + The underlying <span class="bold"><strong>tree implementation</strong></span> type + (<code class="computeroutput"><a class="link" href="../boost/container/tree_type.html" title="Struct template tree_type">tree_type</a></code>). + By default these containers use a red-black tree but the user can use + other tree types: + <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "> +<li class="listitem"> + <a href="http://en.wikipedia.org/wiki/Red%E2%80%93black_tree" target="_top">Red-Black + Tree</a> + </li> +<li class="listitem"> + <a href="http://en.wikipedia.org/wiki/Avl_trees" target="_top">AVL tree</a> + </li> +<li class="listitem"> + <a href="http://en.wikipedia.org/wiki/Scapegoat_tree" target="_top">Scapegoat + tree</a>. In this case Insertion and Deletion are amortized + O(log n) instead of O(log n). + </li> +<li class="listitem"> + <a href="http://en.wikipedia.org/wiki/Splay_tree" target="_top">Splay tree</a>. + In this case Searches, Insertions and Deletions are amortized O(log + n) instead of O(log n). + </li> +</ul></div> + </li> +<li class="listitem"> + Whether the <span class="bold"><strong>size saving</strong></span> mechanisms are + used to implement the tree nodes (<code class="computeroutput"><a class="link" href="../boost/container/optimize_size.html" title="Struct template optimize_size">optimize_size</a></code>). + By default this option is activated and is only meaningful to red-black + and avl trees (in other cases, this option will be ignored). This option + will try to put rebalancing metadata inside the "parent" pointer + of the node if the pointer type has enough alignment. Usually, due to + alignment issues, the metadata uses the size of a pointer yielding to + four pointer size overhead per node, whereas activating this option usually + leads to 3 pointer size overhead. Although some mask operations must + be performed to extract data from this special "parent" pointer, + in several systems this option also improves performance due to the improved + cache usage produced by the node size reduction. + </li> +</ul></div> +<p> + See the following example to see how <code class="computeroutput"><a class="link" href="../boost/container/tree_assoc_options.html" title="Struct template tree_assoc_options">tree_assoc_options</a></code> + can be used to customize these containers: + </p> +<p> +</p> +<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">container</span><span class="special">/</span><span class="identifier">set</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> + +<span class="comment">//Make sure assertions are active</span> +<span class="preprocessor">#ifdef</span> <span class="identifier">NDEBUG</span> +<span class="preprocessor">#undef</span> <span class="identifier">NDEBUG</span> +<span class="preprocessor">#endif</span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cassert</span><span class="special">></span> + +<span class="keyword">int</span> <span class="identifier">main</span> <span class="special">()</span> +<span class="special">{</span> + <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">container</span><span class="special">;</span> + + <span class="comment">//First define several options</span> + <span class="comment">//</span> + + <span class="comment">//This option specifies an AVL tree based associative container</span> + <span class="keyword">typedef</span> <span class="identifier">tree_assoc_options</span><span class="special"><</span> <span class="identifier">tree_type</span><span class="special"><</span><span class="identifier">avl_tree</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">AVLTree</span><span class="special">;</span> + + <span class="comment">//This option specifies an AVL tree based associative container</span> + <span class="comment">//disabling node size optimization.</span> + <span class="keyword">typedef</span> <span class="identifier">tree_assoc_options</span><span class="special"><</span> <span class="identifier">tree_type</span><span class="special"><</span><span class="identifier">avl_tree</span><span class="special">></span> + <span class="special">,</span> <span class="identifier">optimize_size</span><span class="special"><</span><span class="keyword">false</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">AVLTreeNoSizeOpt</span><span class="special">;</span> + + <span class="comment">//This option specifies an Splay tree based associative container</span> + <span class="keyword">typedef</span> <span class="identifier">tree_assoc_options</span><span class="special"><</span> <span class="identifier">tree_type</span><span class="special"><</span><span class="identifier">splay_tree</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">SplayTree</span><span class="special">;</span> + + <span class="comment">//Now define new tree-based associative containers</span> + <span class="comment">//</span> + + <span class="comment">//AVLTree based set container</span> + <span class="keyword">typedef</span> <span class="identifier">set</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">allocator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">AVLTree</span><span class="special">></span> <span class="identifier">AvlSet</span><span class="special">;</span> + + <span class="comment">//AVLTree based set container without size optimization</span> + <span class="keyword">typedef</span> <span class="identifier">set</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">allocator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">AVLTreeNoSizeOpt</span><span class="special">></span> <span class="identifier">AvlSetNoSizeOpt</span><span class="special">;</span> + + <span class="comment">//Splay tree based multiset container</span> + <span class="keyword">typedef</span> <span class="identifier">multiset</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">less</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">allocator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">SplayTree</span><span class="special">></span> <span class="identifier">SplayMultiset</span><span class="special">;</span> + + <span class="comment">//Use them</span> + <span class="comment">//</span> + <span class="identifier">AvlSet</span> <span class="identifier">avl_set</span><span class="special">;</span> + <span class="identifier">avl_set</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">0</span><span class="special">);</span> + <span class="identifier">assert</span><span class="special">(</span><span class="identifier">avl_set</span><span class="special">.</span><span class="identifier">find</span><span class="special">(</span><span class="number">0</span><span class="special">)</span> <span class="special">!=</span> <span class="identifier">avl_set</span><span class="special">.</span><span class="identifier">end</span><span class="special">());</span> + + <span class="identifier">AvlSetNoSizeOpt</span> <span class="identifier">avl_set_no_szopt</span><span class="special">;</span> + <span class="identifier">avl_set_no_szopt</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">1</span><span class="special">);</span> + <span class="identifier">avl_set_no_szopt</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">1</span><span class="special">);</span> + <span class="identifier">assert</span><span class="special">(</span><span class="identifier">avl_set_no_szopt</span><span class="special">.</span><span class="identifier">count</span><span class="special">(</span><span class="number">1</span><span class="special">)</span> <span class="special">==</span> <span class="number">1</span><span class="special">);</span> + + <span class="identifier">SplayMultiset</span> <span class="identifier">splay_mset</span><span class="special">;</span> + <span class="identifier">splay_mset</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">2</span><span class="special">);</span> + <span class="identifier">splay_mset</span><span class="special">.</span><span class="identifier">insert</span><span class="special">(</span><span class="number">2</span><span class="special">);</span> + <span class="identifier">assert</span><span class="special">(</span><span class="identifier">splay_mset</span><span class="special">.</span><span class="identifier">count</span><span class="special">(</span><span class="number">2</span><span class="special">)</span> <span class="special">==</span> <span class="number">2</span><span class="special">);</span> + <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> +<span class="special">}</span> +</pre> +<p> + </p> +</div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="container.configurable_containers.configurable_vectors"></a><a class="link" href="configurable_containers.html#container.configurable_containers.configurable_vectors" title="Configurable vectors">Configurable + vectors</a> +</h3></div></div></div> +<p> + <span class="bold"><strong>Boost.Container</strong></span> offers the possibility to + configure at compile time some parameters of <code class="computeroutput"><a class="link" href="../boost/container/vector.html" title="Class template vector">vector</a></code> + implementation. This configuration is passed as the last template parameter + and defined using the utility class <code class="computeroutput"><a class="link" href="../boost/container/vector_options.html" title="Struct template vector_options">vector_options</a></code>. + The following parameters can be configured: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + <code class="computeroutput"><a class="link" href="../boost/container/growth_factor.html" title="Struct template growth_factor">growth_factor</a></code>: + the growth policy of the vector. The rate at which the capacity of a + vector grows is implementation dependent and implementations choose exponential + growth in order to meet the amortized constant time requirement for push_back. + A higher growth factor will make it faster as it will require less data + movement, but it will have a greater memory impact (on average, more + memory will be unused). A user can provide it's own implementation and + some predefined policies are available: <code class="computeroutput"><a class="link" href="../boost/container/growth_factor_50.html" title="Struct growth_factor_50">growth_factor_50</a></code>, + <code class="computeroutput"><a class="link" href="../boost/container/growth_factor_60.html" title="Struct growth_factor_60">growth_factor_60</a></code> + and <code class="computeroutput"><a class="link" href="../boost/container/growth_factor_50.html" title="Struct growth_factor_50">growth_factor_100</a></code>. + </li> +<li class="listitem"> + <code class="computeroutput"><a class="link" href="../boost/container/stored_size.html" title="Struct template stored_size">stored_size</a></code>: + the type that will be used to store size-related parameters inside of + the vector. Sometimes, when the maximum capacity to be used is much less + than the theoretical maximum that a vector can hold, it's interesting + to use smaller unsigned integer types to represent <code class="computeroutput"><span class="identifier">size</span><span class="special">()</span></code> and <code class="computeroutput"><span class="identifier">capacity</span><span class="special">()</span></code> inside vector, so that the size of + an empty vector is minimized and cache performance might be improved. + See <code class="computeroutput"><a class="link" href="../boost/container/stored_size.html" title="Struct template stored_size">stored_size</a></code> + for more details. + </li> +</ul></div> +<p> + See the following example to see how <code class="computeroutput"><a class="link" href="../boost/container/vector_options.html" title="Struct template vector_options">vector_options</a></code> + can be used to customize <code class="computeroutput"><span class="identifier">vector</span></code> + container: + </p> +<p> +</p> +<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">container</span><span class="special">/</span><span class="identifier">vector</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="keyword">static_assert</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> + +<span class="comment">//Make sure assertions are active</span> +<span class="preprocessor">#ifdef</span> <span class="identifier">NDEBUG</span> +<span class="preprocessor">#undef</span> <span class="identifier">NDEBUG</span> +<span class="preprocessor">#endif</span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cassert</span><span class="special">></span> + +<span class="keyword">int</span> <span class="identifier">main</span> <span class="special">()</span> +<span class="special">{</span> + <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">container</span><span class="special">;</span> + + <span class="comment">//This option specifies that a vector that will use "unsigned char" as</span> + <span class="comment">//the type to store capacity or size internally.</span> + <span class="keyword">typedef</span> <span class="identifier">vector_options</span><span class="special"><</span> <span class="identifier">stored_size</span><span class="special"><</span><span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">size_option_t</span><span class="special">;</span> + + <span class="comment">//Size-optimized vector is smaller than the default one.</span> + <span class="keyword">typedef</span> <span class="identifier">vector</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">new_allocator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">size_option_t</span> <span class="special">></span> <span class="identifier">size_optimized_vector_t</span><span class="special">;</span> + <span class="identifier">BOOST_STATIC_ASSERT</span><span class="special">((</span> <span class="keyword">sizeof</span><span class="special">(</span><span class="identifier">size_optimized_vector_t</span><span class="special">)</span> <span class="special"><</span> <span class="keyword">sizeof</span><span class="special">(</span><span class="identifier">vector</span><span class="special"><</span><span class="keyword">int</span><span class="special">>)</span> <span class="special">));</span> + + <span class="comment">//Requesting capacity for more elements than representable by "unsigned char"</span> + <span class="comment">//is an error in the size optimized vector.</span> + <span class="keyword">bool</span> <span class="identifier">exception_thrown</span> <span class="special">=</span> <span class="keyword">false</span><span class="special">;</span> + <span class="keyword">try</span> <span class="special">{</span> <span class="identifier">size_optimized_vector_t</span> <span class="identifier">v</span><span class="special">(</span><span class="number">256</span><span class="special">);</span> <span class="special">}</span> + <span class="keyword">catch</span><span class="special">(...){</span> <span class="identifier">exception_thrown</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">;</span> <span class="special">}</span> + <span class="identifier">assert</span><span class="special">(</span><span class="identifier">exception_thrown</span> <span class="special">==</span> <span class="keyword">true</span><span class="special">);</span> + + <span class="comment">//This option specifies that a vector will increase its capacity 50%</span> + <span class="comment">//each time the previous capacity was exhausted.</span> + <span class="keyword">typedef</span> <span class="identifier">vector_options</span><span class="special"><</span> <span class="identifier">growth_factor</span><span class="special"><</span><span class="identifier">growth_factor_50</span><span class="special">></span> <span class="special">>::</span><span class="identifier">type</span> <span class="identifier">growth_50_option_t</span><span class="special">;</span> + + <span class="comment">//Fill the vector until full capacity is reached</span> + <span class="identifier">vector</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span> <span class="identifier">new_allocator</span><span class="special"><</span><span class="keyword">int</span><span class="special">>,</span> <span class="identifier">growth_50_option_t</span> <span class="special">></span> <span class="identifier">growth_50_vector</span><span class="special">(</span><span class="number">5</span><span class="special">,</span> <span class="number">0</span><span class="special">);</span> + <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">old_cap</span> <span class="special">=</span> <span class="identifier">growth_50_vector</span><span class="special">.</span><span class="identifier">capacity</span><span class="special">();</span> + <span class="identifier">growth_50_vector</span><span class="special">.</span><span class="identifier">resize</span><span class="special">(</span><span class="identifier">old_cap</span><span class="special">);</span> + + <span class="comment">//Now insert an additional item and check the new buffer is 50% bigger</span> + <span class="identifier">growth_50_vector</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="number">1</span><span class="special">);</span> + <span class="identifier">assert</span><span class="special">(</span><span class="identifier">growth_50_vector</span><span class="special">.</span><span class="identifier">capacity</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">old_cap</span><span class="special">*</span><span class="number">3</span><span class="special">/</span><span class="number">2</span><span class="special">);</span> + + <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> +<span class="special">}</span> +</pre> +<p> + </p> +</div> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2009-2017 Ion + Gaztanaga<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>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="extended_functionality.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../container.html"><img src="../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="extended_allocators.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |