1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Macro BOOST_PROTO_REPEAT_FROM_TO</title> 6<link rel="stylesheet" href="../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="proto/reference.html#header.boost.proto.repeat_hpp" title="Header <boost/proto/repeat.hpp>"> 10<link rel="prev" href="BOOST_PROTO_REPEAT.html" title="Macro BOOST_PROTO_REPEAT"> 11<link rel="next" href="BOOST_PROTO_REPEAT_EX.html" title="Macro BOOST_PROTO_REPEAT_EX"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../boost.png"></td> 16<td align="center"><a href="../../index.html">Home</a></td> 17<td align="center"><a href="../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="BOOST_PROTO_REPEAT.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="proto/reference.html#header.boost.proto.repeat_hpp"><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_PROTO_REPEAT_EX.html"><img src="../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="BOOST_PROTO_REPEAT_FROM_TO"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Macro BOOST_PROTO_REPEAT_FROM_TO</span></h2> 30<p>BOOST_PROTO_REPEAT_FROM_TO — Repeatedly invoke the specified macro.</p> 31</div> 32<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 33<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="proto/reference.html#header.boost.proto.repeat_hpp" title="Header <boost/proto/repeat.hpp>">boost/proto/repeat.hpp</a>> 34 35</span>BOOST_PROTO_REPEAT_FROM_TO(FROM, TO, MACRO)</pre></div> 36<div class="refsect1"> 37<a name="id-1.3.33.5.39.5.4"></a><h2>Description</h2> 38<p> 39 <code class="computeroutput">BOOST_PROTO_REPEAT_FROM_TO()</code> is used to generate the kind of repetitive 40 code that is typical of EDSLs built with Proto. 41 <code class="computeroutput">BOOST_PROTO_REPEAT_FROM_TO(<em class="replaceable"><code>FROM</code></em>, <em class="replaceable"><code>TO</code></em>, <em class="replaceable"><code>MACRO</code></em>)</code> 42 is equivalent to: 43 </p> 44<p> 45 </p> 46<pre class="programlisting"><em class="replaceable"><code><span class="identifier">MACRO</span></code></em><span class="special">(</span><em class="replaceable"><code><span class="identifier">FROM</span></code></em><span class="special">,</span> <a class="link" href="BOOST_PROTO_typename_A.html" title="Macro BOOST_PROTO_typename_A">BOOST_PROTO_typename_A</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref.html" title="Macro BOOST_PROTO_A_const_ref">BOOST_PROTO_A_const_ref</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref_a.html" title="Macro BOOST_PROTO_A_const_ref_a">BOOST_PROTO_A_const_ref_a</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_ref_a.html" title="Macro BOOST_PROTO_ref_a">BOOST_PROTO_ref_a</a><span class="special">)</span> 47<em class="replaceable"><code><span class="identifier">MACRO</span></code></em><span class="special">(</span><em class="replaceable"><code><span class="identifier">FROM</span><span class="special">+</span><span class="number">1</span></code></em><span class="special">,</span> <a class="link" href="BOOST_PROTO_typename_A.html" title="Macro BOOST_PROTO_typename_A">BOOST_PROTO_typename_A</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref.html" title="Macro BOOST_PROTO_A_const_ref">BOOST_PROTO_A_const_ref</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref_a.html" title="Macro BOOST_PROTO_A_const_ref_a">BOOST_PROTO_A_const_ref_a</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_ref_a.html" title="Macro BOOST_PROTO_ref_a">BOOST_PROTO_ref_a</a><span class="special">)</span> 48<span class="special">...</span> 49<em class="replaceable"><code><span class="identifier">MACRO</span></code></em><span class="special">(</span><em class="replaceable"><code><span class="identifier">TO</span><span class="special">-</span><span class="number">1</span></code></em><span class="special">,</span> <a class="link" href="BOOST_PROTO_typename_A.html" title="Macro BOOST_PROTO_typename_A">BOOST_PROTO_typename_A</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref.html" title="Macro BOOST_PROTO_A_const_ref">BOOST_PROTO_A_const_ref</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_A_const_ref_a.html" title="Macro BOOST_PROTO_A_const_ref_a">BOOST_PROTO_A_const_ref_a</a><span class="special">,</span> <a class="link" href="BOOST_PROTO_ref_a.html" title="Macro BOOST_PROTO_ref_a">BOOST_PROTO_ref_a</a><span class="special">)</span></pre> 50<p> 51 </p> 52<p> 53 <span class="bold"><strong>Example:</strong></span> 54 </p> 55<p> 56 </p> 57<pre class="programlisting"><span class="comment">// Generate BOOST_PROTO_MAX_ARITY-1 overloads of the</span> 58<span class="comment">// following construct() function template.</span> 59<span class="preprocessor">#define</span> <span class="identifier">M0</span><span class="special">(</span><span class="identifier">N</span><span class="special">,</span> <span class="identifier">typename_A</span><span class="special">,</span> <span class="identifier">A_const_ref</span><span class="special">,</span> <span class="identifier">A_const_ref_a</span><span class="special">,</span> <span class="identifier">ref_a</span><span class="special">)</span> \ 60<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> <span class="identifier">typename_A</span><span class="special">(</span><span class="identifier">N</span><span class="special">)</span><span class="special">></span> \ 61<span class="keyword">typename</span> <a class="link" href="boost/proto/result_of/make_expr.html" title="Struct template make_expr">proto::result_of::make_expr</a><span class="special"><</span> \ 62 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> \ 63 <span class="special">,</span> <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span> \ 64 <span class="special">,</span> <span class="identifier">A_const_ref</span><span class="special">(</span><span class="identifier">N</span><span class="special">)</span> \ 65<span class="special">></span><span class="special">::</span><span class="identifier">type</span> <span class="keyword">const</span> \ 66<span class="identifier">construct</span><span class="special">(</span><span class="identifier">A_const_ref_a</span><span class="special">(</span><span class="identifier">N</span><span class="special">)</span><span class="special">)</span> \ 67<span class="special">{</span> \ 68 <span class="keyword">return</span> <a class="link" href="boost/proto/make_expr.html" title="Function make_expr">proto::make_expr</a><span class="special"><</span> \ 69 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> \ 70 <span class="special">></span><span class="special">(</span> \ 71 <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span><span class="special">(</span><span class="special">)</span> \ 72 <span class="special">,</span> <span class="identifier">ref_a</span><span class="special">(</span><span class="identifier">N</span><span class="special">)</span> \ 73 <span class="special">)</span><span class="special">;</span> \ 74<span class="special">}</span> 75<span class="identifier">BOOST_PROTO_REPEAT_FROM_TO</span><span class="special">(</span><span class="number">1</span><span class="special">,</span> <span class="identifier">BOOST_PROTO_MAX_ARITY</span><span class="special">,</span> <span class="identifier">M0</span><span class="special">)</span> 76<span class="preprocessor">#undef</span> <span class="identifier">M0</span></pre> 77<p> 78 </p> 79<p> 80 The above invocation of <code class="computeroutput">BOOST_PROTO_REPEAT_FROM_TO()</code> 81 will generate the following code: 82 </p> 83<p> 84 </p> 85<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">A0</span><span class="special">></span> 86<span class="keyword">typename</span> <a class="link" href="boost/proto/result_of/make_expr.html" title="Struct template make_expr">proto::result_of::make_expr</a><span class="special"><</span> 87 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> 88 <span class="special">,</span> <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span> 89 <span class="special">,</span> <span class="identifier">A0</span> <span class="keyword">const</span> <span class="special">&</span> 90<span class="special">></span><span class="special">::</span><span class="identifier">type</span> <span class="keyword">const</span> 91<span class="identifier">construct</span><span class="special">(</span><span class="identifier">A0</span> <span class="keyword">const</span> <span class="special">&</span> <span class="identifier">a0</span><span class="special">)</span> 92<span class="special">{</span> 93 <span class="keyword">return</span> <a class="link" href="boost/proto/make_expr.html" title="Function make_expr">proto::make_expr</a><span class="special"><</span> 94 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> 95 <span class="special">></span><span class="special">(</span> 96 <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span><span class="special">(</span><span class="special">)</span> 97 <span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a0</span><span class="special">)</span> 98 <span class="special">)</span><span class="special">;</span> 99<span class="special">}</span> 100 101<span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">A0</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">A1</span><span class="special">></span> 102<span class="keyword">typename</span> <a class="link" href="boost/proto/result_of/make_expr.html" title="Struct template make_expr">proto::result_of::make_expr</a><span class="special"><</span> 103 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> 104 <span class="special">,</span> <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span> 105 <span class="special">,</span> <span class="identifier">A0</span> <span class="keyword">const</span> <span class="special">&</span> 106 <span class="special">,</span> <span class="identifier">A1</span> <span class="keyword">const</span> <span class="special">&</span> 107<span class="special">></span><span class="special">::</span><span class="identifier">type</span> <span class="keyword">const</span> 108<span class="identifier">construct</span><span class="special">(</span><span class="identifier">A0</span> <span class="keyword">const</span> <span class="special">&</span> <span class="identifier">a0</span><span class="special">,</span> <span class="identifier">A1</span> <span class="keyword">const</span> <span class="special">&</span> <span class="identifier">a1</span><span class="special">)</span> 109<span class="special">{</span> 110 <span class="keyword">return</span> <a class="link" href="boost/proto/make_expr.html" title="Function make_expr">proto::make_expr</a><span class="special"><</span> 111 <a class="link" href="boost/proto/tag/function.html" title="Struct function">proto::tag::function</a> 112 <span class="special">></span><span class="special">(</span> 113 <span class="identifier">construct_helper</span><span class="special"><</span><span class="identifier">T</span><span class="special">></span><span class="special">(</span><span class="special">)</span> 114 <span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a0</span><span class="special">)</span> 115 <span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">a1</span><span class="special">)</span> 116 <span class="special">)</span><span class="special">;</span> 117<span class="special">}</span> 118 119<span class="comment">// ... and so on, up to BOOST_PROTO_MAX_ARITY-1 arguments ...</span></pre> 120<p> 121 </p> 122</div> 123</div> 124<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 125<td align="left"></td> 126<td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p> 127 Distributed under the Boost Software License, Version 1.0. (See accompanying 128 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>) 129 </p> 130</div></td> 131</tr></table> 132<hr> 133<div class="spirit-nav"> 134<a accesskey="p" href="BOOST_PROTO_REPEAT.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="proto/reference.html#header.boost.proto.repeat_hpp"><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_PROTO_REPEAT_EX.html"><img src="../../doc/src/images/next.png" alt="Next"></a> 135</div> 136</body> 137</html> 138
