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| author | Chanho Park <chanho61.park@samsung.com> | 2014-12-11 18:55:56 +0900 |
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| committer | Chanho Park <chanho61.park@samsung.com> | 2014-12-11 18:55:56 +0900 |
| commit | 08c1e93fa36a49f49325a07fe91ff92c964c2b6c (patch) | |
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diff --git a/doc/html/boost_typeerasure.html b/doc/html/boost_typeerasure.html new file mode 100644 index 0000000000..d95b55e3f9 --- /dev/null +++ b/doc/html/boost_typeerasure.html @@ -0,0 +1,210 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Chapter 33. Boost.TypeErasure</title> +<link rel="stylesheet" href="../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +<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="tribool/tests.html" title="Testsuite"> +<link rel="next" href="boost_typeerasure/reading.html" title="How to read this documentation"> +</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="tribool/tests.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="boost_typeerasure/reading.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="boost_typeerasure"></a>Chapter 33. Boost.TypeErasure</h2></div> +<div><div class="author"><h3 class="author"> +<span class="firstname">Steven</span> <span class="surname">Watanabe</span> +</h3></div></div> +<div><p class="copyright">Copyright © 2011-2013 Steven Watanabe</p></div> +<div><div class="legalnotice"> +<a name="boost_typeerasure.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="boost_typeerasure.html#boost_typeerasure.introduction">Introduction</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reading.html">How to read this documentation</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/basic.html">Basic Usage</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/composing_concepts.html">Composing Concepts</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/multi.html">Functions with Multiple Arguments</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/concept.html">Concepts in Depth</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="boost_typeerasure/concept.html#boost_typeerasure.concept.custom">Defining Custom Concepts</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/concept.html#boost_typeerasure.concept.overload">Overloading</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/concept.html#boost_typeerasure.concept.concept_map">Concept Maps</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/concept.html#boost_typeerasure.concept.overload0">Associated Types</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="boost_typeerasure/any.html">Using Any</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="boost_typeerasure/any.html#boost_typeerasure.any.construction">Construction</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/any.html#boost_typeerasure.any.conversions">Conversions</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/any.html#boost_typeerasure.any.references">References</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/any.html#boost_typeerasure.any.limit">Syntax Limitations</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="boost_typeerasure/examples.html">Examples</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="boost_typeerasure/examples.html#boost_typeerasure.examples.print_sequence">A polymorphic + range formatter</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/examples.html#boost_typeerasure.examples.printf">A type-safe printf</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/examples.html#boost_typeerasure.examples.multifunction">Boost.Function + with multiple signatures</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="boost_typeerasure/conceptdef.html">Concept Definitions</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/predef.html">Predefined Concepts</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html">Reference</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.any_hpp">Header <boost/type_erasure/any.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.any_cast_hpp">Header <boost/type_erasure/any_cast.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.binding_hpp">Header <boost/type_erasure/binding.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.binding_of_hpp">Header <boost/type_erasure/binding_of.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.builtin_hpp">Header <boost/type_erasure/builtin.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.call_hpp">Header <boost/type_erasure/call.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.callable_hpp">Header <boost/type_erasure/callable.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.check_match_hpp">Header <boost/type_erasure/check_match.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.concept_interface_hpp">Header <boost/type_erasure/concept_interface.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.concept_of_hpp">Header <boost/type_erasure/concept_of.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.config_hpp">Header <boost/type_erasure/config.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.constructible_hpp">Header <boost/type_erasure/constructible.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.deduced_hpp">Header <boost/type_erasure/deduced.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.derived_hpp">Header <boost/type_erasure/derived.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.exception_hpp">Header <boost/type_erasure/exception.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.free_hpp">Header <boost/type_erasure/free.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.is_empty_hpp">Header <boost/type_erasure/is_empty.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.is_placeholder_hpp">Header <boost/type_erasure/is_placeholder.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.is_subconcept_hpp">Header <boost/type_erasure/is_subconcept.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.iterator_hpp">Header <boost/type_erasure/iterator.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.member_hpp">Header <boost/type_erasure/member.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.operators_hpp">Header <boost/type_erasure/operators.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.param_hpp">Header <boost/type_erasure/param.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.placeholder_hpp">Header <boost/type_erasure/placeholder.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.placeholder_of_hpp">Header <boost/type_erasure/placeholder_of.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.rebind_any_hpp">Header <boost/type_erasure/rebind_any.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.relaxed_hpp">Header <boost/type_erasure/relaxed.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.require_match_hpp">Header <boost/type_erasure/require_match.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.same_type_hpp">Header <boost/type_erasure/same_type.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.static_binding_hpp">Header <boost/type_erasure/static_binding.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.tuple_hpp">Header <boost/type_erasure/tuple.hpp></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/reference.html#header.boost.type_erasure.typeid_of_hpp">Header <boost/type_erasure/typeid_of.hpp></a></span></dt> +</dl></dd> +<dt><span class="section"><a href="boost_typeerasure/rationale.html">Rationale</a></span></dt> +<dd><dl> +<dt><span class="section"><a href="boost_typeerasure/rationale.html#boost_typeerasure.rationale.why_do_i_have_to_specify_the_presence_of_a_destructor_explicitly_">Why + do I have to specify the presence of a destructor explicitly?</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/rationale.html#boost_typeerasure.rationale.why_non_member_functions_">Why + non-member functions?</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/rationale.html#boost_typeerasure.rationale.placeholder">Why are the + placeholders called <code class="computeroutput"><span class="identifier">_a</span></code>, <code class="computeroutput"><span class="identifier">_b</span></code> and not <code class="computeroutput"><span class="identifier">_1</span></code> + <code class="computeroutput"><span class="identifier">_2</span></code></a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/rationale.html#boost_typeerasure.rationale.ref">Why not use <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span></code> + for references?</a></span></dt> +</dl></dd> +<dt><span class="section"><a href="boost_typeerasure/future.html">Future Work</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/acknowledgements.html">Acknowledgements</a></span></dt> +<dt><span class="section"><a href="boost_typeerasure/related.html">Related Work</a></span></dt> +</dl> +</div> +<div class="section"> +<div class="titlepage"><div><div><h2 class="title" style="clear: both"> +<a name="boost_typeerasure.introduction"></a><a class="link" href="boost_typeerasure.html#boost_typeerasure.introduction" title="Introduction">Introduction</a> +</h2></div></div></div> +<p> + The Boost.TypeErasure library provides runtime polymorphism in C++ that is + more flexible than that provided by the core language. + </p> +<p> + C++ has two distinct kinds of polymorphism, virtual functions and templates, + each of which has its own advantages and disadvantages. + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + Virtual functions are not resolved until runtime, while templates are always + resolved at compile time. If your types can vary at runtime (for example, + if they depend on user input), then static polymorphism with templates + doesn't help much. + </li> +<li class="listitem"> + Virtual functions can be used with separate compilation. The body of a + template has to be available in every translation unit in which it is used, + slowing down compiles and increasing rebuilds. + </li> +<li class="listitem"> + Virtual functions automatically make the requirements on the arguments + explicit. Templates are only checked when they're instantiated, requiring + extra work in testing, assertions, and documentation. + </li> +<li class="listitem"> + The compiler creates a new copy of each function template every time it + is instantiated. This allows better optimization, because the compiler + knows everything statically, but it also causes a significant increase + of binary sizes. + </li> +<li class="listitem"> + Templates support Value semantics. Objects that "behave like an int" + and are not shared are easier to reason about. To use virtual functions, + on the other hand, you have to use (smart) pointers or references. + </li> +<li class="listitem"> + Template libraries can allow third-party types to be adapted non-intrusively + for seamless interoperability. With virtual functions, you have to create + a wrapper that inherits from the base class. + </li> +<li class="listitem"> + Templates can handle constraints involving multiple types. For example, + std::for_each takes an iterator range and a function that can be called + on the elements of the range. Virtual functions aren't really able to express + such constraints. + </li> +</ul></div> +<p> + The Boost.TypeErasure library combines the superior abstraction capabilities + of templates, with the runtime flexibility of virtual functions. + </p> +<p> + Boost includes several special cases of this kind of polymorphism: + </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">any</span></code> for CopyConstructible types. + </li> +<li class="listitem"> + <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">function</span></code> for objects that can be called + like functions. + </li> +<li class="listitem"> + Boost.Range provides <code class="computeroutput"><span class="identifier">any_iterator</span></code>. + </li> +</ul></div> +<p> + Boost.TypeErasure generalizes this to support arbitrary requirements and provides + a <a class="link" href="boost_typeerasure/predef.html" title="Predefined Concepts">predefined set of common concepts</a> + </p> +</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: October 30, 2014 at 10:20:49 GMT</small></p></td> +<td align="right"><div class="copyright-footer"></div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="tribool/tests.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="boost_typeerasure/reading.html"><img src="../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |