106 lines
6.5 KiB
HTML
106 lines
6.5 KiB
HTML
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
|
<title>Macro BOOST_TTI_HAS_TEMPLATE</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="Chapter 1. The Type Traits Introspection Library">
|
|
<link rel="up" href="header/boost/tti/has_template_hpp.html" title="Header <boost/tti/has_template.hpp>">
|
|
<link rel="prev" href="BOOST_TTI_TRAIT_HAS_TEMPLATE.html" title="Macro BOOST_TTI_TRAIT_HAS_TEMPLATE">
|
|
<link rel="next" href="header/boost/tti/has_type_hpp.html" title="Header <boost/tti/has_type.hpp>">
|
|
</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="BOOST_TTI_TRAIT_HAS_TEMPLATE.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="header/boost/tti/has_template_hpp.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="header/boost/tti/has_type_hpp.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
|
|
</div>
|
|
<div class="refentry">
|
|
<a name="BOOST_TTI_HAS_TEMPLATE"></a><div class="titlepage"></div>
|
|
<div class="refnamediv">
|
|
<h2><span class="refentrytitle">Macro BOOST_TTI_HAS_TEMPLATE</span></h2>
|
|
<p>BOOST_TTI_HAS_TEMPLATE — Expands to a metafunction which tests whether an inner class template with a particular name exists. </p>
|
|
</div>
|
|
<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
|
|
<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="header/boost/tti/has_template_hpp.html" title="Header <boost/tti/has_template.hpp>">boost/tti/has_template.hpp</a>>
|
|
|
|
</span>BOOST_TTI_HAS_TEMPLATE(...)</pre></div>
|
|
<div class="refsect1">
|
|
<a name="idp48417496"></a><h2>Description</h2>
|
|
<p>... = variadic parameters. The first variadic parameter is the inner class template name.
|
|
|
|
Following variadic parameters are optional.
|
|
|
|
If no following variadic parameters exist, then the inner class template
|
|
being introspected must be all template type parameters ( template parameters
|
|
starting with `class` or `typename` ) and any number of template type parameters
|
|
can occur.
|
|
|
|
If the second variadic parameter is BOOST_PP_NIL and no other variadic
|
|
parameter is given, then just as in the previous case the inner class template
|
|
being introspected must be all template type parameters ( template parameters
|
|
starting with `class` or `typename` ) and any number of template type parameters
|
|
can occur. This form is allowed in order to be consistent with using the
|
|
non-variadic form of this macro.
|
|
|
|
If the second variadic parameter is a Boost preprocessor library array and no other
|
|
variadic parameter is given, then the inner class template must have its template
|
|
parameters matching the sequence in the tuple portion of the Boost PP array. This
|
|
form is allowed in order to be consistent with using the non-variadic form of this
|
|
macro.
|
|
|
|
Otherwise the inner class template must have its template parameters matching the
|
|
sequence of the optional variadic parameters.
|
|
</p>
|
|
<p>generates a metafunction called "has_template_'name'" where 'name' is the first variadic parameter. template<class BOOST_TTI_TP_T>
|
|
struct has_template_'name'
|
|
{
|
|
static const value = unspecified;
|
|
typedef mpl::bool_<true-or-false> type;
|
|
};
|
|
|
|
The metafunction types and return:
|
|
|
|
BOOST_TTI_TP_T = the enclosing type in which to look for our 'name'.
|
|
|
|
returns = 'value' is true if the 'name' template exists within the enclosing type,
|
|
otherwise 'value' is false.
|
|
</p>
|
|
<p>Examples:</p>
|
|
<p>1) Search for an inner class template called 'MyTemplate', with all template type parameters, nested within the class 'MyClass'.</p>
|
|
<p>BOOST_TTI_HAS_TEMPLATE(MyTemplate)</p>
|
|
<p>or</p>
|
|
<p>BOOST_TTI_HAS_TEMPLATE(MyTemplate,BOOST_PP_NIL) // Non-variadic macro form</p>
|
|
<p>has_template_MyTemplate<MyClass>::value</p>
|
|
<p>is a compile time boolean constant which is either 'true' or 'false' if the nested template exists.</p>
|
|
<p>2) Search for an inner class template called 'MyTemplate' with template parameters of 'class T,int x,template<class> class U' nested within the class 'MyClass'.</p>
|
|
<p>BOOST_TTI_HAS_TEMPLATE(MyTemplate,class,int,template<class> class)</p>
|
|
<p>or</p>
|
|
<p>BOOST_TTI_HAS_TEMPLATE(MyTemplate,(3,(class,int,template<class> class))) // Non-variadic macro form</p>
|
|
<p>has_template_MyTemplate<MyClass>::value</p>
|
|
<p>is a compile time boolean constant which is either 'true' or 'false' if the nested template exists. </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 © 2011-2013 Tropic Software
|
|
East Inc<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="BOOST_TTI_TRAIT_HAS_TEMPLATE.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="header/boost/tti/has_template_hpp.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="header/boost/tti/has_type_hpp.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
|
|
</div>
|
|
</body>
|
|
</html>
|