Boost Char Delimiters Separator

Note: This class is deprecated. Please use `char_separator` instead.

# Char Delimiters Separator

    template <class Char, class Traits = std::char_traits<Char> >
    class char_delimiters_separator{

The char_delimiters_separator class is an implementation of the TokenizerFunction 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.

## Example

    // 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";
       }
    }

## Construction and Usage

There is one constructor of interest. It is as follows

    explicit char_delimiters_separator(bool return_delims = false,
    const Char* returnable = "",const Char* nonreturnable = "" )

Parameter | Description
return_delims | 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.
returnable | 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.
nonreturnable | 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.

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.

To use this class, pass an object of it anywhere a TokenizerFunction object is required.

### Template Parameters

Parameter | Description
--- | ---
`Char` | The type of the elements within a token, typically `char`.
Traits | The traits class for Char, typically std::char_traits<Char>

## Model of

TokenizerFunction

Revised 25 December, 2006

Copyright © 2001 John R. Bandela

Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)