feedc0de/boost_iterator
1
0
Fork 0
forked from boostorg/iterator
Code Pull Requests Activity
Files
ab372a0a74319d660bd29406c567f77a261c57a2
boost_iterator/doc/iterator_traits.html

121 lines
5.4 KiB
HTML
Raw Normal View History

Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
Stop reserving rights. [SVN r26085]
2004-11-02 14:31:27 +00:00
<meta name="generator" content="Docutils 0.3.6: http://docutils.sourceforge.net/" />
Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
<title>Iterator Traits</title>
<meta name="author" content="David Abrahams" />
<meta name="organization" content="Boost Consulting" />
Stop reserving rights. [SVN r26085]
2004-11-02 14:31:27 +00:00
<meta name="date" content="2004-11-01" />
<meta name="copyright" content="Copyright David Abrahams 2004." />
Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
<link rel="stylesheet" href="default.css" type="text/css" />
</head>
<body>
<h1 class="title">Iterator Traits</h1>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Author:</th>
<td>David Abrahams</td></tr>
<tr><th class="docinfo-name">Contact:</th>
<td><a class="first last reference" href="mailto:dave&#64;boost-consulting.com">dave&#64;boost-consulting.com</a></td></tr>
<tr><th class="docinfo-name">Organization:</th>
<td><a class="first last reference" href="http://www.boost-consulting.com">Boost Consulting</a></td></tr>
<tr><th class="docinfo-name">Date:</th>
Stop reserving rights. [SVN r26085]
2004-11-02 14:31:27 +00:00
<td>2004-11-01</td></tr>
Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
<tr><th class="docinfo-name">Copyright:</th>
Stop reserving rights. [SVN r26085]
2004-11-02 14:31:27 +00:00
<td>Copyright David Abrahams 2004.</td></tr>
Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
</tbody>
</table>
Stop reserving rights. [SVN r26085]
2004-11-02 14:31:27 +00:00
<div class="document" id="iterator-traits">
Fixed PDF format as article Added iterator_traits docs [SVN r22043]
2004-01-29 05:55:26 +00:00
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field"><th class="field-name">abstract:</th><td class="field-body">Header <tt class="literal"><span class="pre">&lt;boost/iterator/iterator_traits.hpp&gt;</span></tt> provides
the ability to access an iterator's associated types using
MPL-compatible <a class="reference" href="../../mpl/doc/index.html#metafunctions">metafunctions</a>.</td>
</tr>
</tbody>
</table>
<div class="section" id="overview">
<h1><a name="overview">Overview</a></h1>
<p><tt class="literal"><span class="pre">std::iterator_traits</span></tt> provides access to five associated types
of any iterator: its <tt class="literal"><span class="pre">value_type</span></tt>, <tt class="literal"><span class="pre">reference</span></tt>, <tt class="literal"><span class="pre">pointer</span></tt>,
<tt class="literal"><span class="pre">iterator_category</span></tt>, and <tt class="literal"><span class="pre">difference_type</span></tt>. Unfortunately,
such a &quot;multi-valued&quot; traits template can be difficult to use in a
metaprogramming context. <tt class="literal"><span class="pre">&lt;boost/iterator/iterator_traits.hpp&gt;</span></tt>
provides access to these types using a standard <a class="reference" href="../../mpl/doc/index.html#metafunctions">metafunctions</a>.</p>
</div>
<div class="section" id="summary">
<h1><a name="summary">Summary</a></h1>
<p>Header <tt class="literal"><span class="pre">&lt;boost/iterator/iterator_traits.hpp&gt;</span></tt>:</p>
<pre class="literal-block">
template &lt;class Iterator&gt;
struct iterator_value
{
typedef typename
std::iterator_traits&lt;Iterator&gt;::value_type
type;
};
template &lt;class Iterator&gt;
struct iterator_reference
{
typedef typename
std::iterator_traits&lt;Iterator&gt;::reference
type;
};
template &lt;class Iterator&gt;
struct iterator_pointer
{
typedef typename
std::iterator_traits&lt;Iterator&gt;::pointer
type;
};
template &lt;class Iterator&gt;
struct iterator_difference
{
typedef typename
detail::iterator_traits&lt;Iterator&gt;::difference_type
type;
};
template &lt;class Iterator&gt;
struct iterator_category
{
typedef typename
detail::iterator_traits&lt;Iterator&gt;::iterator_category
type;
};
</pre>
</div>
<div class="section" id="broken-compiler-notes">
<h1><a name="broken-compiler-notes">Broken Compiler Notes</a></h1>
<p>Because of workarounds in Boost, you may find that these
<a class="reference" href="../../mpl/doc/index.html#metafunctions">metafunctions</a> actually work better than the facilities provided by
your compiler's standard library.</p>
<p>On compilers that don't support partial specialization, such as
Microsoft Visual C++ 6.0 or 7.0, you may need to manually invoke
<a class="reference" href="../../type_traits/index.html#transformations">BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION</a> on the
<tt class="literal"><span class="pre">value_type</span></tt> of pointers that are passed to these metafunctions.</p>
<p>Because of bugs in the implementation of GCC-2.9x, the name of
<tt class="literal"><span class="pre">iterator_category</span></tt> is changed to <tt class="literal"><span class="pre">iterator_category_</span></tt> on that
compiler. A macro, <tt class="literal"><span class="pre">BOOST_ITERATOR_CATEGORY</span></tt>, that expands to
either <tt class="literal"><span class="pre">iterator_category</span></tt> or <tt class="literal"><span class="pre">iterator_category_</span></tt>, as
appropriate to the platform, is provided for portability.</p>
</div>
</div>
<hr class="footer" />
<div class="footer">
<a class="reference" href="iterator_traits.rst">View document source</a>.
Generated by <a class="reference" href="http://docutils.sourceforge.net/">Docutils</a> from <a class="reference" href="http://docutils.sourceforge.net/rst.html">reStructuredText</a> source.
</div>
</body>
</html>
Copy Permalink