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diff --git a/libs/spirit/doc/html/spirit/qi/tutorials/sum___adding_numbers.html b/libs/spirit/doc/html/spirit/qi/tutorials/sum___adding_numbers.html new file mode 100755 index 0000000000..12c10cabd7 --- /dev/null +++ b/libs/spirit/doc/html/spirit/qi/tutorials/sum___adding_numbers.html @@ -0,0 +1,233 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Sum - adding numbers</title> +<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../../../index.html" title="Spirit 2.5.2"> +<link rel="up" href="../tutorials.html" title="Tutorials"> +<link rel="prev" href="complex___our_first_complex_parser.html" title="Complex - Our first complex parser"> +<link rel="next" href="number_list___stuffing_numbers_into_a_std__vector.html" title="Number List - stuffing numbers into a std::vector"> +</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="complex___our_first_complex_parser.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorials.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="number_list___stuffing_numbers_into_a_std__vector.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h4 class="title"> +<a name="spirit.qi.tutorials.sum___adding_numbers"></a><a class="link" href="sum___adding_numbers.html" title="Sum - adding numbers">Sum - adding + numbers</a> +</h4></div></div></div> +<p> + Here's a parser that sums a comma-separated list of numbers. + </p> +<p> + Ok we've glossed over some details in our previous examples. First, our + includes: + </p> +<p> +</p> +<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">qi</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">phoenix_core</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">spirit</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">phoenix_operator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> +<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">string</span><span class="special">></span> +</pre> +<p> + </p> +<p> + Then some using directives: + </p> +<p> +</p> +<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">qi</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">qi</span><span class="special">;</span> +<span class="keyword">namespace</span> <span class="identifier">ascii</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">ascii</span><span class="special">;</span> +<span class="keyword">namespace</span> <span class="identifier">phoenix</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">;</span> + +<span class="keyword">using</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">double_</span><span class="special">;</span> +<span class="keyword">using</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">_1</span><span class="special">;</span> +<span class="keyword">using</span> <span class="identifier">ascii</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span> +<span class="keyword">using</span> <span class="identifier">phoenix</span><span class="special">::</span><span class="identifier">ref</span><span class="special">;</span> +</pre> +<p> + </p> +<div class="informaltable"><table class="table"> +<colgroup> +<col> +<col> +</colgroup> +<thead><tr> +<th> + <p> + Namespace + </p> + </th> +<th> + <p> + Description + </p> + </th> +</tr></thead> +<tbody> +<tr> +<td> + <p> + boost::phoenix + </p> + </td> +<td> + <p> + All of phoenix + </p> + </td> +</tr> +<tr> +<td> + <p> + boost::spirit + </p> + </td> +<td> + <p> + All of spirit + </p> + </td> +</tr> +<tr> +<td> + <p> + boost::spirit::qi + </p> + </td> +<td> + <p> + All of spirit.qi + </p> + </td> +</tr> +<tr> +<td> + <p> + boost::spirit::ascii + </p> + </td> +<td> + <p> + ASCII version of <code class="computeroutput"><span class="identifier">char_</span></code> + and all char related parsers. Other encodings are also provided + (e.g. also an ISO8859.1) + </p> + </td> +</tr> +<tr> +<td> + <p> + boost::spirit::arg_names + </p> + </td> +<td> + <p> + Special phoenix placeholders for spirit + </p> + </td> +</tr> +</tbody> +</table></div> +<div class="note"><table border="0" summary="Note"> +<tr> +<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../images/note.png"></td> +<th align="left">Note</th> +</tr> +<tr><td align="left" valign="top"><p> + If you feel uneasy with using whole namespaces, feel free to qualify + your code, use namespace aliases, etc. For the purpose of this tutorial, + we will be presenting unqualified names for both Spirit and <a href="../../../../../phoenix/doc/html/index.html" target="_top">Phoenix</a>. + No worries, we will always present the full working code, so you won't + get lost. In fact, all examples in this tutorial have a corresponding + cpp file that QuickBook (the documentation tool we are using) imports + in here as code snippets. + </p></td></tr> +</table></div> +<p> + Now the actual parser: + </p> +<p> +</p> +<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">></span> +<span class="keyword">bool</span> <span class="identifier">adder</span><span class="special">(</span><span class="identifier">Iterator</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">Iterator</span> <span class="identifier">last</span><span class="special">,</span> <span class="keyword">double</span><span class="special">&</span> <span class="identifier">n</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">bool</span> <span class="identifier">r</span> <span class="special">=</span> <span class="identifier">qi</span><span class="special">::</span><span class="identifier">phrase_parse</span><span class="special">(</span><span class="identifier">first</span><span class="special">,</span> <span class="identifier">last</span><span class="special">,</span> + + <span class="comment">// Begin grammar</span> + <span class="special">(</span> + <span class="identifier">double_</span><span class="special">[</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">=</span> <span class="identifier">_1</span><span class="special">]</span> <span class="special">>></span> <span class="special">*(</span><span class="char">','</span> <span class="special">>></span> <span class="identifier">double_</span><span class="special">[</span><span class="identifier">ref</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">+=</span> <span class="identifier">_1</span><span class="special">])</span> + <span class="special">)</span> + <span class="special">,</span> + <span class="comment">// End grammar</span> + + <span class="identifier">space</span><span class="special">);</span> + + <span class="keyword">if</span> <span class="special">(</span><span class="identifier">first</span> <span class="special">!=</span> <span class="identifier">last</span><span class="special">)</span> <span class="comment">// fail if we did not get a full match</span> + <span class="keyword">return</span> <span class="keyword">false</span><span class="special">;</span> + <span class="keyword">return</span> <span class="identifier">r</span><span class="special">;</span> +<span class="special">}</span> +</pre> +<p> + </p> +<p> + The full cpp file for this example can be found here: <a href="../../../../../example/qi/sum.cpp" target="_top">../../example/qi/sum.cpp</a> + </p> +<p> + This is almost like our original numbers list example. We're incrementally + building on top of our examples. This time though, like in the complex + number example, we'll be adding the smarts. There's an accumulator (<code class="computeroutput"><span class="keyword">double</span><span class="special">&</span> <span class="identifier">n</span></code>) that adds the numbers parsed. On a + successful parse, this number is the sum of all the parsed numbers. + </p> +<p> + The first <code class="computeroutput"><span class="identifier">double_</span></code> parser + attaches this action: + </p> +<pre class="programlisting"><span class="identifier">ref</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">=</span> <span class="identifier">_1</span> +</pre> +<p> + This assigns the parsed result (actually, the attribute of <code class="computeroutput"><span class="identifier">double_</span></code>) to <code class="computeroutput"><span class="identifier">n</span></code>. + <code class="computeroutput"><span class="identifier">ref</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code> tells + <a href="../../../../../phoenix/doc/html/index.html" target="_top">Phoenix</a> that <code class="computeroutput"><span class="identifier">n</span></code> is a mutable reference. <code class="computeroutput"><span class="identifier">_1</span></code> is a <a href="../../../../../phoenix/doc/html/index.html" target="_top">Phoenix</a> + placeholder for the parsed result attribute. + </p> +<p> + The second <code class="computeroutput"><span class="identifier">double_</span></code> parser + attaches this action: + </p> +<pre class="programlisting"><span class="identifier">ref</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span> <span class="special">+=</span> <span class="identifier">_1</span> +</pre> +<p> + So, subsequent numbers add into <code class="computeroutput"><span class="identifier">n</span></code>. + </p> +<p> + That wasn't too bad, was it :-) ? + </p> +</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 © 2001-2011 Joel de Guzman, Hartmut Kaiser<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="complex___our_first_complex_parser.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorials.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="number_list___stuffing_numbers_into_a_std__vector.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |