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<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>
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<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>
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