| <html> |
| <head> |
| <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> |
| <title>Separate Output Into Columns (columns[])</title> |
| <link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> |
| <meta name="generator" content="DocBook XSL Stylesheets V1.75.0"> |
| <link rel="home" href="../../../../index.html" title="Spirit 2.4.1"> |
| <link rel="up" href="../directive.html" title="Directive"> |
| <link rel="prev" href="duplicate.html" title="Duplicate Attribute (duplicate[])"> |
| <link rel="next" href="../nonterminal.html" title="Nonterminal"> |
| </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="duplicate.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directive.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="../nonterminal.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> |
| </div> |
| <div class="section"> |
| <div class="titlepage"><div><div><h5 class="title"> |
| <a name="spirit.karma.reference.directive.columns"></a><a class="link" href="columns.html" title="Separate Output Into Columns (columns[])">Separate |
| Output Into Columns (<code class="computeroutput"><span class="identifier">columns</span><span class="special">[]</span></code>)</a> |
| </h5></div></div></div> |
| <a name="spirit.karma.reference.directive.columns.description"></a><h6> |
| <a name="id1056905"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.description">Description</a> |
| </h6> |
| <p> |
| The <code class="computeroutput"><span class="identifier">columns</span><span class="special">[]</span></code> |
| directive separates the output emitted by the embedded generator by inserting |
| special column separators. |
| </p> |
| <a name="spirit.karma.reference.directive.columns.header"></a><h6> |
| <a name="id1056933"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.header">Header</a> |
| </h6> |
| <pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/karma/directive/columns.hpp> |
| </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">karma_columns</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> |
| </pre> |
| <p> |
| Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>. |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup><col></colgroup> |
| <thead><tr><th> |
| <p> |
| Name |
| </p> |
| </th></tr></thead> |
| <tbody><tr><td> |
| <p> |
| <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">columns</span> <span class="comment">// |
| alias: boost::spirit::karma::columns</span></code> |
| </p> |
| </td></tr></tbody> |
| </table></div> |
| <a name="spirit.karma.reference.directive.columns.model_of"></a><h6> |
| <a name="id1057073"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.model_of">Model |
| of</a> |
| </h6> |
| <div class="blockquote"><blockquote class="blockquote"><p> |
| <a class="link" href="../generator_concepts/unarygenerator.html" title="UnaryGenerator"><code class="computeroutput"><span class="identifier">UnaryGenerator</span></code></a> |
| </p></blockquote></div> |
| <div class="variablelist"> |
| <p class="title"><b>Notation</b></p> |
| <dl> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">a</span></code></span></dt> |
| <dd><p> |
| A generator object |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">g</span></code></span></dt> |
| <dd><p> |
| A generator object, or a <a class="link" href="../karma_basics.html#spirit.karma.reference.karma_basics.lazy_argument">Lazy |
| Argument</a> that evaluates to a generator object, will be used |
| to emit column separators |
| </p></dd> |
| <dt><span class="term"><code class="computeroutput"><span class="identifier">A</span></code></span></dt> |
| <dd> |
| <p> |
| Attribute type of generator <code class="computeroutput"><span class="identifier">a</span></code> |
| </p> |
| <p> |
| [<code class="computeroutput"><span class="identifier">num</span></code> |
| </p> |
| <p> |
| Numeric literal, any unsigned integer value, or a <a class="link" href="../karma_basics.html#spirit.karma.reference.karma_basics.lazy_argument">Lazy |
| Argument</a> that evaluates to an unsigned integer value defining |
| the number of items to emit in between the column separators |
| </p> |
| </dd> |
| </dl> |
| </div> |
| <a name="spirit.karma.reference.directive.columns.expression_semantics"></a><h6> |
| <a name="id1057204"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.expression_semantics">Expression |
| Semantics</a> |
| </h6> |
| <p> |
| Semantics of an expression is defined only where it differs from, or |
| is not defined in <a class="link" href="../generator_concepts/unarygenerator.html" title="UnaryGenerator"><code class="computeroutput"><span class="identifier">UnaryGenerator</span></code></a>. |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Expression |
| </p> |
| </th> |
| <th> |
| <p> |
| Semantics |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The <code class="computeroutput"><span class="identifier">columns</span></code> |
| directive invokes a generator after each N-th element of the |
| embedded generator has been emitted. The number of columns |
| is defined by the preprocessor constant <code class="computeroutput"><span class="identifier">BOOST_KARMA_DEFAULT_COLUMNS</span></code>. |
| The column separator used will be <code class="computeroutput"><span class="identifier">karma</span><span class="special">::</span><span class="identifier">eol</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The <code class="computeroutput"><span class="identifier">columns</span></code> |
| directive invokes a generator after each N-th element of the |
| embedded generator has been emitted. The number of columns |
| is defined by the argument to the directive <code class="computeroutput"><span class="identifier">num</span></code>. |
| The column separator used will be <code class="computeroutput"><span class="identifier">karma</span><span class="special">::</span><span class="identifier">eol</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The <code class="computeroutput"><span class="identifier">columns</span></code> |
| directive invokes a generator after each N-th element of the |
| embedded generator has been emitted. The number of columns |
| is defined by the preprocessor constant <code class="computeroutput"><span class="identifier">BOOST_KARMA_DEFAULT_COLUMNS</span></code>. |
| The column separator used will be <code class="computeroutput"><span class="identifier">g</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">,</span> |
| <span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| The <code class="computeroutput"><span class="identifier">columns</span></code> |
| directive invokes a generator after each N-th element of the |
| embedded generator has been emitted. The number of columns |
| is defined by the argument to the directive <code class="computeroutput"><span class="identifier">num</span></code>. |
| The column separator used will be <code class="computeroutput"><span class="identifier">g</span></code>. |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <a name="spirit.karma.reference.directive.columns.attributes"></a><h6> |
| <a name="id1057550"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.attributes">Attributes</a> |
| </h6> |
| <p> |
| See <a class="link" href="../../quick_reference/compound_attribute_rules.html#spirit.karma.quick_reference.compound_attribute_rules.notation">Compound |
| Attribute Notation</a>. |
| </p> |
| <div class="informaltable"><table class="table"> |
| <colgroup> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| Expression |
| </p> |
| </th> |
| <th> |
| <p> |
| Attribute |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| |
| </p> |
| <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">A</span> |
| <span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">Unused</span></pre> |
| <p> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| |
| </p> |
| <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">A</span> |
| <span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">Unused</span></pre> |
| <p> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| |
| </p> |
| <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">A</span> |
| <span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">Unused</span></pre> |
| <p> |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">,</span> |
| <span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| |
| </p> |
| <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">,</span> <span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">A</span> |
| <span class="identifier">a</span><span class="special">:</span> <span class="identifier">Unused</span> <span class="special">--></span> <span class="identifier">columns</span><span class="special">(</span><span class="identifier">num</span><span class="special">,</span> <span class="identifier">g</span><span class="special">)[</span><span class="identifier">a</span><span class="special">]:</span> <span class="identifier">Unused</span></pre> |
| <p> |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| <a name="spirit.karma.reference.directive.columns.complexity"></a><h6> |
| <a name="id1058159"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.complexity">Complexity</a> |
| </h6> |
| <div class="blockquote"><blockquote class="blockquote"><p> |
| The overall complexity of the <code class="computeroutput"><span class="identifier">columns</span></code> |
| generator directive depends on the complexity of the embedded generator. |
| The complexity of the <code class="computeroutput"><span class="identifier">columns</span></code> |
| generator directive itself is O(N), where <code class="computeroutput"><span class="identifier">N</span></code> |
| is the number of inserted column separators. |
| </p></blockquote></div> |
| <a name="spirit.karma.reference.directive.columns.example"></a><h6> |
| <a name="id1058202"></a> |
| <a class="link" href="columns.html#spirit.karma.reference.directive.columns.example">Example</a> |
| </h6> |
| <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> |
| The test harness for the example(s) below is presented in the <a class="link" href="../karma_basics.html#spirit.karma.reference.karma_basics.examples">Basics Examples</a> |
| section. |
| </p></td></tr> |
| </table></div> |
| <p> |
| Some 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">karma</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">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">std_pair</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> |
| Some using declarations: |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">karma</span><span class="special">::</span><span class="identifier">double_</span><span class="special">;</span> |
| <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">karma</span><span class="special">::</span><span class="identifier">columns</span><span class="special">;</span> |
| <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">spirit</span><span class="special">::</span><span class="identifier">karma</span><span class="special">::</span><span class="identifier">space</span><span class="special">;</span> |
| </pre> |
| <p> |
| </p> |
| <p> |
| Basic usage of the <code class="computeroutput"><span class="identifier">columns</span></code> |
| generators: |
| </p> |
| <p> |
| |
| </p> |
| <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="keyword">double</span><span class="special">></span> <span class="identifier">v</span><span class="special">;</span> |
| <span class="identifier">v</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="number">1.0</span><span class="special">);</span> |
| <span class="identifier">v</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="number">2.0</span><span class="special">);</span> |
| <span class="identifier">v</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="number">3.0</span><span class="special">);</span> |
| <span class="identifier">test_generator_attr</span><span class="special">(</span><span class="string">"1.0\n2.0\n3.0\n"</span><span class="special">,</span> <span class="identifier">columns</span><span class="special">(</span><span class="number">1</span><span class="special">)[*</span><span class="identifier">double_</span><span class="special">],</span> <span class="identifier">v</span><span class="special">);</span> |
| <span class="identifier">test_generator_attr_delim</span><span class="special">(</span><span class="string">"1.0 2.0 \n3.0 \n"</span><span class="special">,</span> <span class="identifier">columns</span><span class="special">(</span><span class="number">2</span><span class="special">)[*</span><span class="identifier">double_</span><span class="special">],</span> <span class="identifier">space</span><span class="special">,</span> <span class="identifier">v</span><span class="special">);</span> |
| </pre> |
| <p> |
| </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 © 2001-2010 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="duplicate.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../directive.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="../nonterminal.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> |
| </div> |
| </body> |
| </html> |
