<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Language" content="en-us"> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="GENERATOR" content="Microsoft FrontPage 6.0"> <meta name="ProgId" content="FrontPage.Editor.Document"> <title>Boost Char Delimiters Separator</title> </head> <body bgcolor="#FFFFFF" text="#000000" link="#0000EE" vlink="#551A8B" alink= "#FF0000"> <p><img src="../../boost.png" alt="C++ Boost" width="277" height= "86"><br></p><font color="red">Note: This class is deprecated. Please use <a href="char_separator.htm"><tt>char_separator</tt></a> instead.</font> <h1 align="center">Char Delimiters Separator</h1> <pre> template <class Char, class Traits = std::char_traits<Char> > class char_delimiters_separator{ </pre> <p>The char_delimiters_separator class is an implementation of the <a href= "tokenizerfunction.htm">TokenizerFunction</a> concept that can be used to break text up into tokens. It is the default TokenizerFunction for tokenizer and token_iterator_generator. An example is below.</p> <h2>Example</h2> <pre> // simple_example_4.cpp #include<iostream> #include<boost/tokenizer.hpp> #include<string> int main(){ using namespace std; using namespace boost; string s = "This is, a test"; tokenizer<char_delimiters_separator<char> > tok(s); for(tokenizer<char_delimiters_separator<char> >::iterator beg=tok.begin(); beg!=tok.end();++beg){ cout << *beg << "\n"; } } </pre> <h2>Construction and Usage</h2> <p>There is one constructor of interest. It is as follows</p> <pre> explicit char_delimiters_separator(bool return_delims = false, const Char* returnable = "",const Char* nonreturnable = "" ) </pre> <table border="1" summary=""> <tr> <td> <p align="center"><strong>Parameter</strong></p> </td> <td> <p align="center"><strong>Description</strong></p> </td> </tr> <tr> <td>return_delims</td> <td>Whether or not to return the delimiters that have been found. Note that not all delimiters can be returned. See the other two parameters for explanation.</td> </tr> <tr> <td>returnable</td> <td>This specifies the returnable delimiters. These are the delimiters that can be returned as tokens when return_delims is true. Since these are typically punctuation, if a 0 is provided as the argument, then the returnable delmiters will be all characters Cfor which std::ispunct(C) yields a true value. If an argument of "" is provided, then this is taken to mean that there are noreturnable delimiters.</td> </tr> <tr> <td>nonreturnable</td> <td>This specifies the nonreturnable delimiters. These are delimiters that cannot be returned as tokens. Since these are typically whitespace, if 0 is specified as an argument, then the nonreturnable delimiters will be all characters C for which std::isspace(C) yields a true value. If an argument of "" is provided, then this is taken to mean that there are no non-returnable delimiters.</td> </tr> </table> <p>The reason there is a distinction between nonreturnable and returnable delimiters is that some delimiters are just used to split up tokens and are nothing more. Take for example the following string "b c +". Assume you are writing a simple calculator to parse expression in post fix notation. While both the space and the + separate tokens, you only only interested in the + and not in the space. Indeed having the space returned as a token would only complicate your code. In this case you would specify + as a returnable, and space as a nonreturnable delimiter.</p> <p>To use this class, pass an object of it anywhere a TokenizerFunction object is required.</p> <h3>Template Parameters</h3> <table border="1" summary=""> <tr> <th>Parameter</th> <th>Description</th> </tr> <tr> <td><tt>Char</tt></td> <td>The type of the elements within a token, typically <tt>char</tt>.</td> </tr> <tr> <td>Traits</td> <td>The traits class for Char, typically std::char_traits<Char></td> </tr> </table> <h2>Model of</h2> <p><a href="tokenizerfunction.htm">TokenizerFunction</a></p> <p> </p> <hr> <p><a href="http://validator.w3.org/check?uri=referer"><img border="0" src= "../../doc/images/valid-html401.png" alt="Valid HTML 4.01 Transitional" height="31" width="88"></a></p> <p>Revised <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->25 December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38518" --></p> <p><i>Copyright © 2001 John R. Bandela</i></p> <p><i>Distributed under the Boost Software License, Version 1.0. (See accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or copy at <a href= "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p> </body> </html>