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diff --git a/doc/html/poly_collection.html b/doc/html/poly_collection.html new file mode 100644 index 0000000000..715525e0ee --- /dev/null +++ b/doc/html/poly_collection.html @@ -0,0 +1,201 @@ +<!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>Chapter 27. Boost.PolyCollection</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="libraries.html" title="Part I. The Boost C++ Libraries (BoostBook Subset)"> +<link rel="prev" href="auxiliary.html" title="Auxiliary Components"> +<link rel="next" href="poly_collection/an_efficient_polymorphic_data_st.html" title="An efficient polymorphic data structure"> +</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="auxiliary.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="libraries.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="poly_collection/an_efficient_polymorphic_data_st.html"><img src="../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="chapter"> +<div class="titlepage"><div> +<div><h2 class="title"> +<a name="poly_collection"></a>Chapter 27. Boost.PolyCollection</h2></div> +<div><div class="author"><h3 class="author"> +<span class="firstname">Joaquín M</span> <span class="surname">López Muñoz</span> +</h3></div></div> +<div><p class="copyright">Copyright © 2016, 2017 Joaquín M López Muñoz</p></div> +<div><div class="legalnotice"> +<a name="poly_collection.legal"></a><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></div> +</div></div> +<div class="toc"> +<p><b>Table of Contents</b></p> +<dl class="toc"> +<dt><span class="section"><a href="poly_collection.html#poly_collection.introduction">Introduction</a></span></dt> +<dt><span class="section"><a href="poly_collection/an_efficient_polymorphic_data_st.html">An efficient + polymorphic data structure</a></span></dt> +<dt><span class="section"><a href="poly_collection/tutorial.html">Tutorial</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="poly_collection/tutorial.html#poly_collection.tutorial.basics">Basics</a></span></dt> +<dt><span class="section"><a href="poly_collection/tutorial.html#poly_collection.tutorial.deeper_into_the_segmented_nature">Deeper + into the segmented nature of Boost.PolyCollection</a></span></dt> +<dt><span class="section"><a href="poly_collection/tutorial.html#poly_collection.tutorial.insertion_and_emplacement">Insertion + and emplacement</a></span></dt> +<dt><span class="section"><a href="poly_collection/tutorial.html#poly_collection.tutorial.exceptions">Exceptions</a></span></dt> +<dt><span class="section"><a href="poly_collection/tutorial.html#poly_collection.tutorial.algorithms">Algorithms</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="poly_collection/performance.html">Performance</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="poly_collection/performance.html#poly_collection.performance.container_definitions">Container + definitions</a></span></dt> +<dt><span class="section"><a href="poly_collection/performance.html#poly_collection.performance.insertion_tests">Insertion + tests</a></span></dt> +<dt><span class="section"><a href="poly_collection/performance.html#poly_collection.performance.processing_tests">Processing + tests</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="poly_collection/reference.html">Reference</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.polymorphism_models">Polymorphism + models</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.polymorphic_containers">Polymorphic + containers</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_exc">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/exception.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_bas">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/base_collection_fwd.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_ba0">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/base_collection.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_fun">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/function_collection_fwd.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_fu0">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/function_collection.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_any">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/any_collection_fwd.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_an0">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/any_collection.hpp"</span></code> + synopsis</a></span></dt> +<dt><span class="section"><a href="poly_collection/reference.html#poly_collection.reference.header_boost_poly_collection_alg">Header + <code class="computeroutput"><span class="string">"boost/poly_collection/algorithm.hpp"</span></code> + synopsis</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="poly_collection/future_work.html">Future work</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="poly_collection/future_work.html#poly_collection.future_work.alternative_rtti_systems">Alternative + RTTI systems</a></span></dt> +<dt><span class="section"><a href="poly_collection/future_work.html#poly_collection.future_work.copy_traits">Copy traits</a></span></dt> +<dt><span class="section"><a href="poly_collection/future_work.html#poly_collection.future_work.parallel_algorithms">Parallel + algorithms</a></span></dt> +<dt><span class="section"><a href="poly_collection/future_work.html#poly_collection.future_work.variant_collection"><code class="computeroutput"><span class="identifier">variant_collection</span></code></a></span></dt> +<dt><span class="section"><a href="poly_collection/future_work.html#poly_collection.future_work.ordered_polymorphic_collections">Ordered + polymorphic collections</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="poly_collection/release_notes.html">Release notes</a></span></dt> +<dd><dl><dt><span class="section"><a href="poly_collection/release_notes.html#poly_collection.release_notes.boost_1_65">Boost 1.65</a></span></dt></dl></dd> +<dt><span class="section"><a href="poly_collection/acknowledgments.html">Acknowledgments</a></span></dt> +</dl> +</div> +<div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="poly_collection.introduction"></a><a class="link" href="poly_collection.html#poly_collection.introduction" title="Introduction">Introduction</a> +</h2></div></div></div> +<p> + Dynamic polymorphism in C++ requires that objects (such as instances of classes + derived from an abstract base) be accessed through an indirection pointer because + their actual <span class="emphasis"><em>type</em></span> and <span class="emphasis"><em>size</em></span> are not + known at the point of usage. As a consequence, regular containers cannot store + polymorphic objects directly: the usual workaround is to have containers of + pointers to heap-allocated elements. In modern computer architectures this + pattern incurs in two types of inefficiency: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + The lack of memory contiguity produced by heap allocation degrades CPU + cache performance. + </li> +<li class="listitem"> + Executing virtual operations on a sequence of polymorphic objects whose + actual types differ from one to the next results in failures in <a href="https://en.wikipedia.org/wiki/Branch_predictor" target="_top">branch prediction</a> + and a lower execution speed. + </li> +</ul></div> +<p> + When the particular traversal order is not relevant to the user application, + Boost.PolyCollection proposes an alternative data structure that restores memory + contiguity and packs elements according to their concrete type. Three container + class templates are provided: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">base_collection</span></code> + </li> +<li class="listitem"> + <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">function_collection</span></code> + </li> +<li class="listitem"> + <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">any_collection</span></code> + </li> +</ul></div> +<p> + respectively dealing with three different types of dynamic polymorphism available + in C++: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + Classic base/derived or OOP polymorphism. + </li> +<li class="listitem"> + Function wrapping in the spirit of <a href="http://en.cppreference.com/w/cpp/utility/functional/function" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">function</span></code></a>. + </li> +<li class="listitem"> + So-called <a href="https://en.wikipedia.org/wiki/Duck_typing" target="_top"><span class="emphasis"><em>duck + typing</em></span></a> as implemented by <a href="../../libs/type_erasure" target="_top">Boost.TypeErasure</a>. + </li> +</ul></div> +<p> + The interface of these containers closely follows that of standard containers. + Additionally, the library provides versions of many of the standard library + algorithms (including <a href="http://en.cppreference.com/w/cpp/algorithm/for_each" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">for_each</span></code></a>) + with improved performance and a special feature called <span class="emphasis"><em>type restitution</em></span> + that allows user code to provide clues on the concrete types of the elements + stored for further opportunities of increased efficiency related to inlining + and <a href="http://hubicka.blogspot.com.es/2014/01/devirtualization-in-c-part-1.html" target="_top"><span class="emphasis"><em>devirtualization</em></span></a>. + </p> +<div class="note"><table border="0" summary="Note"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../doc/src/images/note.png"></td> +<th align="left">Note</th> +</tr> +<tr><td align="left" valign="top"><p> + Boost.PolyCollection is a header-only library. C++11 support is required. + The library has been verified to work with Visual Studio 2015, GCC 5.2 and + Clang 3.7. + </p></td></tr> +</table></div> +</div> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"><p><small>Last revised: August 19, 2017 at 16:57:06 GMT</small></p></td> +<td align="right"><div class="copyright-footer"></div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="auxiliary.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="libraries.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="poly_collection/an_efficient_polymorphic_data_st.html"><img src="../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |