1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Not-Predicate Generator (!a)</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="../operator.html" title="Generator Operators"> 9<link rel="prev" href="and_predicate.html" title="And-Predicate Generator (&a)"> 10<link rel="next" href="../stream.html" title="Stream Generators"> 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="and_predicate.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../operator.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="../stream.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.operator.not_predicate"></a><a class="link" href="not_predicate.html" title="Not-Predicate Generator (!a)">Not-Predicate 28 Generator (<code class="computeroutput"><span class="special">!</span><span class="identifier">a</span></code>)</a> 29</h5></div></div></div> 30<h6> 31<a name="spirit.karma.reference.operator.not_predicate.h0"></a> 32 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.description"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.description">Description</a> 33 </h6> 34<p> 35 The not-predicate generator is used to test, whether the embedded generator 36 fails, without generating any output. It succeeds if the embedded generator 37 fails. 38 </p> 39<h6> 40<a name="spirit.karma.reference.operator.not_predicate.h1"></a> 41 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.header"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.header">Header</a> 42 </h6> 43<pre class="programlisting"><span class="comment">// forwards to <boost/spirit/home/karma/operator/not_predicate.hpp></span> 44<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_not_predicate</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 45</pre> 46<p> 47 Also, see <a class="link" href="../../../structure/include.html" title="Include">Include Structure</a>. 48 </p> 49<h6> 50<a name="spirit.karma.reference.operator.not_predicate.h2"></a> 51 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.model_of"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.model_of">Model 52 of</a> 53 </h6> 54<div class="blockquote"><blockquote class="blockquote"><p> 55 <a class="link" href="../generator_concepts/unarygenerator.html" title="UnaryGenerator"><code class="computeroutput"><span class="identifier">UnaryGenerator</span></code></a> 56 </p></blockquote></div> 57<h6> 58<a name="spirit.karma.reference.operator.not_predicate.h3"></a> 59 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.expression_semantics"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.expression_semantics">Expression 60 Semantics</a> 61 </h6> 62<p> 63 Semantics of an expression is defined only where it differs from, or 64 is not defined in <a class="link" href="../generator_concepts/unarygenerator.html" title="UnaryGenerator"><code class="computeroutput"><span class="identifier">UnaryGenerator</span></code></a>. 65 </p> 66<div class="informaltable"><table class="table"> 67<colgroup> 68<col> 69<col> 70</colgroup> 71<thead><tr> 72<th> 73 <p> 74 Expression 75 </p> 76 </th> 77<th> 78 <p> 79 Semantics 80 </p> 81 </th> 82</tr></thead> 83<tbody><tr> 84<td> 85 <p> 86 <code class="computeroutput"><span class="special">!</span><span class="identifier">a</span></code> 87 </p> 88 </td> 89<td> 90 <p> 91 The generator <code class="computeroutput"><span class="identifier">a</span></code> 92 is executed for the sole purpose of testing whether it succeeds. 93 The not-predicate generator succeeds if its embedded generator 94 fails (unless the underlying output stream reports an error). 95 The not-predicate never produces any output. 96 </p> 97 </td> 98</tr></tbody> 99</table></div> 100<p> 101 The not generator is implemented by redirecting all output produced by 102 its embedded generator into a discarding device. 103 </p> 104<h6> 105<a name="spirit.karma.reference.operator.not_predicate.h4"></a> 106 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.attributes"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.attributes">Attributes</a> 107 </h6> 108<p> 109 See <a class="link" href="../../quick_reference/compound_attribute_rules.html#spirit.karma.quick_reference.compound_attribute_rules.notation">Compound 110 Attribute Notation</a>. 111 </p> 112<div class="informaltable"><table class="table"> 113<colgroup> 114<col> 115<col> 116</colgroup> 117<thead><tr> 118<th> 119 <p> 120 Expression 121 </p> 122 </th> 123<th> 124 <p> 125 Attribute 126 </p> 127 </th> 128</tr></thead> 129<tbody><tr> 130<td> 131 <p> 132 <code class="computeroutput"><span class="special">!</span><span class="identifier">a</span></code> 133 (not-predicate, unary <code class="computeroutput"><span class="special">!</span></code>) 134 </p> 135 </td> 136<td> 137 <p> 138 <code class="computeroutput"><span class="identifier">a</span><span class="special">:</span> 139 <span class="identifier">A</span> <span class="special">--></span> 140 <span class="special">!</span><span class="identifier">a</span><span class="special">:</span> <span class="identifier">A</span></code> 141 </p> 142 </td> 143</tr></tbody> 144</table></div> 145<div class="note"><table border="0" summary="Note"> 146<tr> 147<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td> 148<th align="left">Note</th> 149</tr> 150<tr><td align="left" valign="top"><p> 151 The attribute of the not-predicate is not always <code class="computeroutput"><span class="identifier">unused_type</span></code>, 152 which is different from Qi's not-predicate. This is necessary as the 153 generator the and-predicate is attached to most of the time needs an 154 attribute. 155 </p></td></tr> 156</table></div> 157<h6> 158<a name="spirit.karma.reference.operator.not_predicate.h5"></a> 159 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.complexity"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.complexity">Complexity</a> 160 </h6> 161<div class="blockquote"><blockquote class="blockquote"><p> 162 The overall complexity of the not-predicate generator is defined by 163 the complexity of its embedded generator. The complexity of the not-predicate 164 generator itself is O(1). 165 </p></blockquote></div> 166<h6> 167<a name="spirit.karma.reference.operator.not_predicate.h6"></a> 168 <span class="phrase"><a name="spirit.karma.reference.operator.not_predicate.example"></a></span><a class="link" href="not_predicate.html#spirit.karma.reference.operator.not_predicate.example">Example</a> 169 </h6> 170<div class="note"><table border="0" summary="Note"> 171<tr> 172<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../images/note.png"></td> 173<th align="left">Note</th> 174</tr> 175<tr><td align="left" valign="top"><p> 176 The test harness for the example(s) below is presented in the <a class="link" href="../basics.html#spirit.karma.reference.basics.examples">Basics Examples</a> 177 section. 178 </p></td></tr> 179</table></div> 180<p> 181 Some includes: 182 </p> 183<p> 184</p> 185<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> 186<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">support_utree</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> 187<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> 188<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> 189<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> 190<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> 191<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">string</span><span class="special">></span> 192</pre> 193<p> 194 </p> 195<p> 196 Some using declarations: 197 </p> 198<p> 199</p> 200<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> 201<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">ascii</span><span class="special">::</span><span class="identifier">char_</span><span class="special">;</span> 202<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">ascii</span><span class="special">::</span><span class="identifier">string</span><span class="special">;</span> 203<span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">::</span><span class="identifier">ref</span><span class="special">;</span> 204</pre> 205<p> 206 </p> 207<p> 208 Basic usage of a not predicate generator: 209 </p> 210<p> 211</p> 212<pre class="programlisting"><span class="identifier">test_generator_attr</span><span class="special">(</span><span class="string">"c"</span><span class="special">,</span> <span class="special">!</span><span class="identifier">char_</span><span class="special">(</span><span class="char">'a'</span><span class="special">)</span> <span class="special"><<</span> <span class="char">'b'</span> <span class="special">|</span> <span class="char">'c'</span><span class="special">,</span> <span class="char">'a'</span><span class="special">);</span> 213<span class="identifier">test_generator_attr</span><span class="special">(</span><span class="string">"b"</span><span class="special">,</span> <span class="special">!</span><span class="identifier">char_</span><span class="special">(</span><span class="char">'a'</span><span class="special">)</span> <span class="special"><<</span> <span class="char">'b'</span> <span class="special">|</span> <span class="char">'c'</span><span class="special">,</span> <span class="char">'x'</span><span class="special">);</span> 214 215<span class="identifier">test_generator_attr</span><span class="special">(</span><span class="string">"def"</span><span class="special">,</span> <span class="special">!</span><span class="identifier">string</span><span class="special">(</span><span class="string">"123"</span><span class="special">)</span> <span class="special"><<</span> <span class="string">"abc"</span> <span class="special">|</span> <span class="string">"def"</span><span class="special">,</span> <span class="string">"123"</span><span class="special">);</span> 216<span class="identifier">test_generator_attr</span><span class="special">(</span><span class="string">"abc"</span><span class="special">,</span> <span class="special">!</span><span class="identifier">string</span><span class="special">(</span><span class="string">"123"</span><span class="special">)</span> <span class="special"><<</span> <span class="string">"abc"</span> <span class="special">|</span> <span class="string">"def"</span><span class="special">,</span> <span class="string">"456"</span><span class="special">);</span> 217</pre> 218<p> 219 </p> 220</div> 221<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 222<td align="left"></td> 223<td align="right"><div class="copyright-footer">Copyright © 2001-2011 Joel de Guzman, Hartmut Kaiser<p> 224 Distributed under the Boost Software License, Version 1.0. (See accompanying 225 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>) 226 </p> 227</div></td> 228</tr></table> 229<hr> 230<div class="spirit-nav"> 231<a accesskey="p" href="and_predicate.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../operator.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="../stream.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 232</div> 233</body> 234</html> 235
