url/grammar/alpha_chars.hpp

0001 //
0002 // Copyright (c) 2021 Vinnie Falco (vinnie dot falco at gmail dot com)
0003 //
0004 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0005 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 //
0007 // Official repository: https://github.com/boostorg/url
0008 //
0009
0010 #ifndef BOOST_URL_GRAMMAR_ALPHA_CHARS_HPP
0011 #define BOOST_URL_GRAMMAR_ALPHA_CHARS_HPP
0012
0013 #include <boost/url/detail/config.hpp>
0014 #include <boost/url/grammar/detail/charset.hpp>
0015
0016 namespace boost {
0017 namespace urls {
0018 namespace grammar {
0019
0020 /** The set of all letters
0021
0022     @par Example
0023     Character sets are used with rules and the
0024     functions @ref find_if and @ref find_if_not.
0025     @code
0026     system::result< core::string_view > rv = parse( "JohnDoe", token_rule( alpha_chars ) );
0027     @endcode
0028
0029     @par BNF
0030     @code
0031     ALPHA       = %x41-5A / %x61-7A
0032                 ; A-Z / a-z
0033     @endcode
0034
0035     @par Specification
0036     @li <a href="https://datatracker.ietf.org/doc/html/rfc5234#appendix-B.1"
0037         >B.1. Core Rules (rfc5234)</a>
0038
0039     @see
0040         @ref find_if,
0041         @ref find_if_not,
0042         @ref parse,
0043         @ref token_rule.
0044 */
0045 #ifdef BOOST_URL_DOCS
0046 constexpr __implementation_defined__ alpha_chars;
0047 #else
0048 struct alpha_chars_t
0049 {
0050     constexpr
0051     alpha_chars_t() noexcept = default;
0052
0053     constexpr
0054     bool
0055     operator()(char c) const noexcept
0056     {
0057         return
0058             (c >= 'A' && c <= 'Z') ||
0059             (c >= 'a' && c <= 'z');
0060     }
0061
0062 #ifdef BOOST_URL_USE_SSE2
0063     char const*
0064     find_if(
0065         char const* first,
0066         char const* last) const noexcept
0067     {
0068         return detail::find_if_pred(
0069             *this, first, last);
0070     }
0071
0072     char const*
0073     find_if_not(
0074         char const* first,
0075         char const* last) const noexcept
0076     {
0077         return detail::find_if_not_pred(
0078             *this, first, last);
0079     }
0080 #endif
0081 };
0082
0083 /** A character set containing the alphabetical characters.
0084
0085     @see
0086         @ref alpha_chars_t
0087 */
0088 constexpr alpha_chars_t alpha_chars{};
0089 #endif
0090
0091 } // grammar
0092 } // urls
0093 } // boost
0094
0095 #endif