1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Stream Based Generator API</title> 5<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../../index.html" title="Spirit 2.5.8"> 8<link rel="up" href="../generate_api.html" title="Generator API"> 9<link rel="prev" href="iterator_api.html" title="Iterator Based Generator API"> 10<link rel="next" href="create_generator.html" title="API for Automatic Generator Creation"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="iterator_api.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../generate_api.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="create_generator.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="spirit.karma.reference.generate_api.stream_api"></a><a class="link" href="stream_api.html" title="Stream Based Generator API">Stream 28 Based Generator API</a> 29</h5></div></div></div> 30<h6> 31<a name="spirit.karma.reference.generate_api.stream_api.h0"></a> 32 <span class="phrase"><a name="spirit.karma.reference.generate_api.stream_api.description"></a></span><a class="link" href="stream_api.html#spirit.karma.reference.generate_api.stream_api.description">Description</a> 33 </h6> 34<p> 35 The library provides a couple of Standard IO <a href="http://www.cppreference.com/wiki/io/io_flags#manipulators" target="_top">Manipulators</a> 36 allowing to integrate <span class="emphasis"><em>Spirit.Karma</em></span> output generation 37 facilities with Standard output streams. These generator manipulators 38 have two forms. The first form, <code class="computeroutput"><span class="identifier">format</span></code>, 39 concatenates the output generated by the involved components without 40 inserting any output in between. The second, <code class="computeroutput"><span class="identifier">format_delimited</span></code>, 41 intersperses the output generated by the involved components using the 42 given delimiter generator. Both versions can take in attributes by (constant) 43 reference that hold the attribute values to output. 44 </p> 45<h6> 46<a name="spirit.karma.reference.generate_api.stream_api.h1"></a> 47 <span class="phrase"><a name="spirit.karma.reference.generate_api.stream_api.header"></a></span><a class="link" href="stream_api.html#spirit.karma.reference.generate_api.stream_api.header">Header</a> 48 </h6> 49<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/karma/stream/format_manip.hpp></span> 50<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_format</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 51</pre> 52<p> 53 For variadic attributes: 54 </p> 55<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/karma/stream/format_manip_attr.hpp></span> 56<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_format_attr</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 57</pre> 58<p> 59 The variadic attributes version of the API allows one or more attributes 60 to be passed into the <code class="computeroutput"><span class="identifier">format</span></code> 61 manipulators. The manipulators taking two or more attributes are usable 62 when the generator expression is a <a class="link" href="../operator/sequence.html" title="Sequence Generator (a << b)">Sequence 63 (<code class="computeroutput"><span class="special"><<</span></code>)</a> only. 64 In this case each of the attributes passed have to match the corresponding 65 part of the sequence. 66 </p> 67<p> 68 For the API functions deducing the correct (matching) generator type 69 from the supplied attribute type: 70 </p> 71<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/karma/format_auto.hpp></span> 72<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_format_auto</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 73</pre> 74<p> 75 Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>. 76 </p> 77<h6> 78<a name="spirit.karma.reference.generate_api.stream_api.h2"></a> 79 <span class="phrase"><a name="spirit.karma.reference.generate_api.stream_api.namespace"></a></span><a class="link" href="stream_api.html#spirit.karma.reference.generate_api.stream_api.namespace">Namespace</a> 80 </h6> 81<div class="informaltable"><table class="table"> 82<colgroup><col></colgroup> 83<thead><tr><th> 84 <p> 85 Name 86 </p> 87 </th></tr></thead> 88<tbody> 89<tr><td> 90 <p> 91 <code class="computeroutput"><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">format</span></code> 92 </p> 93 </td></tr> 94<tr><td> 95 <p> 96 <code class="computeroutput"><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">format_delimited</span></code> 97 </p> 98 </td></tr> 99<tr><td> 100 <p> 101 <code class="computeroutput"><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">delimit_flag</span><span class="special">::</span><span class="identifier">predelimit</span></code> 102 </p> 103 </td></tr> 104<tr><td> 105 <p> 106 <code class="computeroutput"><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">delimit_flag</span><span class="special">::</span><span class="identifier">dont_predelimit</span></code> 107 </p> 108 </td></tr> 109</tbody> 110</table></div> 111<h6> 112<a name="spirit.karma.reference.generate_api.stream_api.h3"></a> 113 <span class="phrase"><a name="spirit.karma.reference.generate_api.stream_api.synopsis"></a></span><a class="link" href="stream_api.html#spirit.karma.reference.generate_api.stream_api.synopsis">Synopsis</a> 114 </h6> 115<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">spirit</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">karma</span> 116<span class="special">{</span> 117 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Expr</span><span class="special">></span> 118 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 119 <span class="identifier">format</span><span class="special">(</span> 120 <span class="identifier">Expr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">xpr</span><span class="special">);</span> 121 122 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Expr</span> 123 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="keyword">typename</span> <span class="identifier">AttrN</span><span class="special">></span> 124 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 125 <span class="identifier">format</span><span class="special">(</span> 126 <span class="identifier">Expr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">xpr</span> 127 <span class="special">,</span> <span class="identifier">Attr1</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr1</span><span class="special">,</span> <span class="identifier">Attr2</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="identifier">AttrN</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attrN</span><span class="special">);</span> 128 129 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Expr</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span><span class="special">></span> 130 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 131 <span class="identifier">format_delimited</span><span class="special">(</span> 132 <span class="identifier">Expr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">expr</span> 133 <span class="special">,</span> <span class="identifier">Delimiter</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">d</span> 134 <span class="special">,</span> <span class="identifier">BOOST_SCOPED_ENUM</span><span class="special">(</span><span class="identifier">delimit_flag</span><span class="special">)</span> <span class="identifier">pre_delimit</span> <span class="special">=</span> <span class="identifier">delimit_flag</span><span class="special">::</span><span class="identifier">dont_predelimit</span><span class="special">);</span> 135 136 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Expr</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span> 137 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="keyword">typename</span> <span class="identifier">AttrN</span><span class="special">></span> 138 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 139 <span class="identifier">format_delimited</span><span class="special">(</span> 140 <span class="identifier">Expr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">expr</span> 141 <span class="special">,</span> <span class="identifier">Delimiter</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">d</span> 142 <span class="special">,</span> <span class="identifier">Attr1</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr1</span><span class="special">,</span> <span class="identifier">Attr2</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="identifier">AttrN</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attrN</span><span class="special">);</span> 143 144 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Expr</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span> 145 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="keyword">typename</span> <span class="identifier">AttrN</span><span class="special">></span> 146 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 147 <span class="identifier">format_delimited</span><span class="special">(</span> 148 <span class="identifier">Expr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">expr</span> 149 <span class="special">,</span> <span class="identifier">Delimiter</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">d</span> 150 <span class="special">,</span> <span class="identifier">BOOST_SCOPED_ENUM</span><span class="special">(</span><span class="identifier">delimit_flag</span><span class="special">)</span> <span class="identifier">pre_delimit</span> 151 <span class="special">,</span> <span class="identifier">Attr1</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr1</span><span class="special">,</span> <span class="identifier">Attr2</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr2</span><span class="special">,</span> <span class="special">...,</span> <span class="identifier">AttrN</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attrN</span><span class="special">);</span> 152<span class="special">}}}</span> 153</pre> 154<p> 155 <span class="emphasis"><em>Spirit.Karma</em></span> generator API functions based on the 156 automatic creation of the matching generator type: 157 </p> 158<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">spirit</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">karma</span> 159<span class="special">{</span> 160 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Attr</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Delimiter</span><span class="special">></span> 161 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 162 <span class="identifier">format_delimited</span><span class="special">(</span> 163 <span class="identifier">Attr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">attr</span> 164 <span class="special">,</span> <span class="identifier">Delimiter</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">d</span> 165 <span class="special">,</span> <span class="identifier">BOOST_SCOPED_ENUM</span><span class="special">(</span><span class="identifier">delimit_flag</span><span class="special">)</span> <span class="identifier">pre_delimit</span> <span class="special">=</span> <span class="identifier">delimit_flag</span><span class="special">::</span><span class="identifier">dont_predelimit</span><span class="special">);</span> 166 167 <span class="keyword">template</span> <span class="special"><</span><span class="keyword">typename</span> <span class="identifier">Attr</span><span class="special">></span> 168 <span class="keyword">inline</span> <span class="special"><</span><span class="identifier">unspecified</span><span class="special">></span> 169 <span class="identifier">format</span><span class="special">(</span> 170 <span class="identifier">Attr</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">xpr</span><span class="special">);</span> 171<span class="special">}}}</span> 172</pre> 173<p> 174 All functions above return a standard IO stream manipulator instance 175 (see <a href="http://www.cppreference.com/wiki/io/io_flags#manipulators" target="_top">Manipulators</a>), 176 which when streamed to an output stream will result in generating the 177 output as emitted by the embedded <span class="emphasis"><em>Spirit.Karma</em></span> generator 178 expression. Any error occurring during the invocation of the <span class="emphasis"><em>Spirit.Karma</em></span> 179 generators will be reflected in the streams status flag (<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">ios_base</span><span class="special">::</span><span class="identifier">failbit</span></code> will be set). 180 </p> 181<p> 182 The maximum number of supported arguments is limited by the preprocessor 183 constant <code class="computeroutput"><span class="identifier">SPIRIT_ARGUMENTS_LIMIT</span></code>. 184 This constant defaults to the value defined by the preprocessor constant 185 <code class="computeroutput"><span class="identifier">PHOENIX_LIMIT</span></code> (which 186 in turn defaults to <code class="computeroutput"><span class="number">10</span></code>). 187 </p> 188<div class="note"><table border="0" summary="Note"> 189<tr> 190<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td> 191<th align="left">Note</th> 192</tr> 193<tr><td align="left" valign="top"><p> 194 The variadic manipulators with two or more attributes internally combine 195 (constant) references to all passed attributes into a <code class="computeroutput"><span class="identifier">fusion</span><span class="special">::</span><span class="identifier">vector</span></code> and forward this as a combined 196 attribute to the corresponding manipulator taking one attribute. 197 </p></td></tr> 198</table></div> 199<p> 200 The <code class="computeroutput"><span class="identifier">format_delimited</span></code> 201 manipulators not taking an explicit <code class="computeroutput"><span class="identifier">delimit_flag</span></code> 202 as one of their arguments don't invoke the passed delimiter before starting 203 to generate output from the generator expression. This can be enabled 204 by using the other version of that manipulator while passing <code class="computeroutput"><span class="identifier">delimit_flag</span><span class="special">::</span><span class="identifier">predelimit</span></code> to the corresponding argument. 205 </p> 206<h6> 207<a name="spirit.karma.reference.generate_api.stream_api.h4"></a> 208 <span class="phrase"><a name="spirit.karma.reference.generate_api.stream_api.template_parameters"></a></span><a class="link" href="stream_api.html#spirit.karma.reference.generate_api.stream_api.template_parameters">Template 209 parameters</a> 210 </h6> 211<div class="informaltable"><table class="table"> 212<colgroup> 213<col> 214<col> 215</colgroup> 216<thead><tr> 217<th> 218 <p> 219 Parameter 220 </p> 221 </th> 222<th> 223 <p> 224 Description 225 </p> 226 </th> 227</tr></thead> 228<tbody> 229<tr> 230<td> 231 <p> 232 <code class="computeroutput"><span class="identifier">Expr</span></code> 233 </p> 234 </td> 235<td> 236 <p> 237 An expression that can be converted to a Karma generator. 238 </p> 239 </td> 240</tr> 241<tr> 242<td> 243 <p> 244 <code class="computeroutput"><span class="identifier">Delimiter</span></code> 245 </p> 246 </td> 247<td> 248 <p> 249 Generator used to delimit the output of the expression components. 250 </p> 251 </td> 252</tr> 253<tr> 254<td> 255 <p> 256 <code class="computeroutput"><span class="identifier">Attr</span></code> 257 </p> 258 </td> 259<td> 260 <p> 261 An attribute type utilized to create the corresponding generator 262 type from. 263 </p> 264 </td> 265</tr> 266<tr> 267<td> 268 <p> 269 <code class="computeroutput"><span class="identifier">Attr1</span></code>, <code class="computeroutput"><span class="identifier">Attr2</span></code>, ..., <code class="computeroutput"><span class="identifier">AttrN</span></code> 270 </p> 271 </td> 272<td> 273 <p> 274 One or more attributes. 275 </p> 276 </td> 277</tr> 278</tbody> 279</table></div> 280</div> 281<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 282<td align="left"></td> 283<td align="right"><div class="copyright-footer">Copyright © 2001-2011 Joel de Guzman, Hartmut Kaiser<p> 284 Distributed under the Boost Software License, Version 1.0. (See accompanying 285 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>) 286 </p> 287</div></td> 288</tr></table> 289<hr> 290<div class="spirit-nav"> 291<a accesskey="p" href="iterator_api.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../generate_api.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="create_generator.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 292</div> 293</body> 294</html> 295
