boost_1_45_0/libs/spirit/doc/lex/token_primitives.qbk

[/==============================================================================
    Copyright (C) 2001-2010 Hartmut Kaiser
    Copyright (C) 2001-2010 Joel de Guzman

    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)
===============================================================================/]

[section:primitives Token definition Primitives]

This module includes different primitives allowing you to create token definitions.
It includes `char_`, character literals, `string`, and string literals.

[heading Module Headers]

    // forwards to <boost/spirit/home/lex/primitives.hpp>
    #include <boost/spirit/include/lex_primitives.hpp>

Also, see __include_structure__.

[/////////////////////////////////////////////////////////////////////////////]
[section:char_tokendef Tokens Matching Single Characters]

[heading Description]

The character based token definitions described in this section are:

The `char_` creates token definitions matching single characters. The `char_` 
token definition is associated `standard` encoding namespace. This is 
needed when doing basic operations such as forcing lower or upper case and 
dealing with character ranges.

[heading Header]

[heading Module Headers]

    // forwards to <boost/spirit/home/lex/lexer/char_token_def.hpp>
    #include <boost/spirit/include/lex_char_token_def.hpp>

Also, see __include_structure__.

[heading Namespace]

[table
    [[Name]]
    [[`boost::spirit::lit // alias: boost::spirit::lex::lit` ]]
    [[`lex::char_`]]
]

[heading Model of]

[:__primitive_lexer_concept__]

[variablelist Notation
    [[`ch`]       [Character-class specific character from `standard` character 
                   set.]]
]

[heading Expression Semantics]

Semantics of an expression is defined only where it differs from, or is not
defined in __primitive_lexer_concept__.

[table
    [[Expression]           [Description]]
    [[`ch`]                 [Create a token definition matching the character 
                             literal `ch`. ]]
    [[`lit(ch)`]            [Create a token definition matching the character 
                             literal `ch`. ]]
    [[`lex::char_(ch)`]     [Create a token definition matching the character 
                             `ch`.]]
]

[heading Example]


[endsect] [/ char]

[endsect] [/ Module]