EIC code displayed by LXR master/​include/​boost/​xpressive/​traits/​c_regex_traits.hpp	Source navigation Diff markup Identifier search General search
	Version: master test Revert   Change

File indexing completed on 2025-01-18 09:53:53

 //////////////////////////////////////////////////////////////////////////////
 /// \file c_regex_traits.hpp
 /// Contains the definition of the c_regex_traits\<\> template, which is a
 /// wrapper for the C locale functions that can be used to customize the
 /// behavior of static and dynamic regexes.
 //
 //  Copyright 2008 Eric Niebler. 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)
 
 #ifndef BOOST_XPRESSIVE_TRAITS_C_REGEX_TRAITS_HPP_EAN_10_04_2005
 #define BOOST_XPRESSIVE_TRAITS_C_REGEX_TRAITS_HPP_EAN_10_04_2005
 
 // MS compatible compilers support #pragma once
 #if defined(_MSC_VER)
 # pragma once
 #endif
 
 #include <cstdlib>
 #include <boost/config.hpp>
 #include <boost/assert.hpp>
 #include <boost/xpressive/traits/detail/c_ctype.hpp>
 
 namespace boost { namespace xpressive
 {
 
 namespace detail
 {
     ///////////////////////////////////////////////////////////////////////////////
     // empty_locale
     struct empty_locale
     {
     };
 
     ///////////////////////////////////////////////////////////////////////////////
     // c_regex_traits_base
     template<typename Char, std::size_t SizeOfChar = sizeof(Char)>
     struct c_regex_traits_base
     {
     protected:
         template<typename Traits>
         void imbue(Traits const &tr)
         {
         }
     };
 
     template<typename Char>
     struct c_regex_traits_base<Char, 1>
     {
     protected:
         template<typename Traits>
         static void imbue(Traits const &)
         {
         }
     };
 
     #ifndef BOOST_XPRESSIVE_NO_WREGEX
     template<std::size_t SizeOfChar>
     struct c_regex_traits_base<wchar_t, SizeOfChar>
     {
     protected:
         template<typename Traits>
         static void imbue(Traits const &)
         {
         }
     };
     #endif
 
     template<typename Char>
     Char c_tolower(Char);
 
     template<typename Char>
     Char c_toupper(Char);
 
     template<>
     inline char c_tolower(char ch)
     {
         using namespace std;
         return static_cast<char>(tolower(static_cast<unsigned char>(ch)));
     }
 
     template<>
     inline char c_toupper(char ch)
     {
         using namespace std;
         return static_cast<char>(toupper(static_cast<unsigned char>(ch)));
     }
 
     #ifndef BOOST_XPRESSIVE_NO_WREGEX
     template<>
     inline wchar_t c_tolower(wchar_t ch)
     {
         using namespace std;
         return towlower(ch);
     }
 
     template<>
     inline wchar_t c_toupper(wchar_t ch)
     {
         using namespace std;
         return towupper(ch);
     }
     #endif
 
 } // namespace detail
 
 ///////////////////////////////////////////////////////////////////////////////
 // regex_traits_version_1_tag
 //
 struct regex_traits_version_1_tag;
 
 ///////////////////////////////////////////////////////////////////////////////
 // c_regex_traits
 //
 /// \brief Encapsaulates the standard C locale functions for use by the
 /// \c basic_regex\<\> class template.
 template<typename Char>
 struct c_regex_traits
   : detail::c_regex_traits_base<Char>
 {
     typedef Char char_type;
     typedef std::basic_string<char_type> string_type;
     typedef detail::empty_locale locale_type;
     typedef typename detail::char_class_impl<Char>::char_class_type char_class_type;
     typedef regex_traits_version_2_tag version_tag;
     typedef detail::c_regex_traits_base<Char> base_type;
 
     /// Initialize a c_regex_traits object to use the global C locale.
     ///
     c_regex_traits(locale_type const &loc = locale_type())
       : base_type()
     {
         this->imbue(loc);
     }
 
     /// Checks two c_regex_traits objects for equality
     ///
     /// \return true.
     bool operator ==(c_regex_traits<char_type> const &) const
     {
         return true;
     }
 
     /// Checks two c_regex_traits objects for inequality
     ///
     /// \return false.
     bool operator !=(c_regex_traits<char_type> const &) const
     {
         return false;
     }
 
     /// Convert a char to a Char
     ///
     /// \param ch The source character.
     /// \return ch if Char is char, std::btowc(ch) if Char is wchar_t.
     static char_type widen(char ch);
 
     /// Returns a hash value for a Char in the range [0, UCHAR_MAX]
     ///
     /// \param ch The source character.
     /// \return a value between 0 and UCHAR_MAX, inclusive.
     static unsigned char hash(char_type ch)
     {
         return static_cast<unsigned char>(std::char_traits<Char>::to_int_type(ch));
     }
 
     /// No-op
     ///
     /// \param ch The source character.
     /// \return ch
     static char_type translate(char_type ch)
     {
         return ch;
     }
 
     /// Converts a character to lower-case using the current global C locale.
     ///
     /// \param ch The source character.
     /// \return std::tolower(ch) if Char is char, std::towlower(ch) if Char is wchar_t.
     static char_type translate_nocase(char_type ch)
     {
         return detail::c_tolower(ch);
     }
 
     /// Converts a character to lower-case using the current global C locale.
     ///
     /// \param ch The source character.
     /// \return std::tolower(ch) if Char is char, std::towlower(ch) if Char is wchar_t.
     static char_type tolower(char_type ch)
     {
         return detail::c_tolower(ch);
     }
 
     /// Converts a character to upper-case using the current global C locale.
     ///
     /// \param ch The source character.
     /// \return std::toupper(ch) if Char is char, std::towupper(ch) if Char is wchar_t.
     static char_type toupper(char_type ch)
     {
         return detail::c_toupper(ch);
     }
 
     /// Returns a \c string_type containing all the characters that compare equal
     /// disregrarding case to the one passed in. This function can only be called
     /// if <tt>has_fold_case\<c_regex_traits\<Char\> \>::value</tt> is \c true.
     ///
     /// \param ch The source character.
     /// \return \c string_type containing all chars which are equal to \c ch when disregarding
     ///     case
     //typedef array<char_type, 2> fold_case_type;
     string_type fold_case(char_type ch) const
     {
         BOOST_MPL_ASSERT((is_same<char_type, char>));
         char_type ntcs[] = {
             detail::c_tolower(ch)
           , detail::c_toupper(ch)
           , 0
         };
         if(ntcs[1] == ntcs[0])
             ntcs[1] = 0;
         return string_type(ntcs);
     }
 
     /// Checks to see if a character is within a character range.
     ///
     /// \param first The bottom of the range, inclusive.
     /// \param last The top of the range, inclusive.
     /// \param ch The source character.
     /// \return first <= ch && ch <= last.
     static bool in_range(char_type first, char_type last, char_type ch)
     {
         return first <= ch && ch <= last;
     }
 
     /// Checks to see if a character is within a character range, irregardless of case.
     ///
     /// \param first The bottom of the range, inclusive.
     /// \param last The top of the range, inclusive.
     /// \param ch The source character.
     /// \return in_range(first, last, ch) || in_range(first, last, tolower(ch)) || in_range(first,
     ///     last, toupper(ch))
     /// \attention The default implementation doesn't do proper Unicode
     ///     case folding, but this is the best we can do with the standard
     ///     C locale functions.
     static bool in_range_nocase(char_type first, char_type last, char_type ch)
     {
         return c_regex_traits::in_range(first, last, ch)
             || c_regex_traits::in_range(first, last, detail::c_tolower(ch))
             || c_regex_traits::in_range(first, last, detail::c_toupper(ch));
     }
 
     /// Returns a sort key for the character sequence designated by the iterator range [F1, F2)
     /// such that if the character sequence [G1, G2) sorts before the character sequence [H1, H2)
     /// then v.transform(G1, G2) < v.transform(H1, H2).
     ///
     /// \attention Not currently used
     template<typename FwdIter>
     static string_type transform(FwdIter begin, FwdIter end)
     {
         BOOST_ASSERT(false); // BUGBUG implement me
     }
 
     /// Returns a sort key for the character sequence designated by the iterator range [F1, F2)
     /// such that if the character sequence [G1, G2) sorts before the character sequence [H1, H2)
     /// when character case is not considered then
     /// v.transform_primary(G1, G2) < v.transform_primary(H1, H2).
     ///
     /// \attention Not currently used
     template<typename FwdIter>
     static string_type transform_primary(FwdIter begin, FwdIter end)
     {
         BOOST_ASSERT(false); // BUGBUG implement me
     }
 
     /// Returns a sequence of characters that represents the collating element
     /// consisting of the character sequence designated by the iterator range [F1, F2).
     /// Returns an empty string if the character sequence is not a valid collating element.
     ///
     /// \attention Not currently used
     template<typename FwdIter>
     static string_type lookup_collatename(FwdIter begin, FwdIter end)
     {
         BOOST_ASSERT(false); // BUGBUG implement me
     }
 
     /// For the character class name represented by the specified character sequence,
     /// return the corresponding bitmask representation.
     ///
     /// \param begin A forward iterator to the start of the character sequence representing
     ///     the name of the character class.
     /// \param end The end of the character sequence.
     /// \param icase Specifies whether the returned bitmask should represent the case-insensitive
     ///     version of the character class.
     /// \return A bitmask representing the character class.
     template<typename FwdIter>
     static char_class_type lookup_classname(FwdIter begin, FwdIter end, bool icase)
     {
         return detail::char_class_impl<char_type>::lookup_classname(begin, end, icase);
     }
 
     /// Tests a character against a character class bitmask.
     ///
     /// \param ch The character to test.
     /// \param mask The character class bitmask against which to test.
     /// \pre mask is a bitmask returned by lookup_classname, or is several such masks bit-or'ed
     ///     together.
     /// \return true if the character is a member of any of the specified character classes, false
     ///     otherwise.
     static bool isctype(char_type ch, char_class_type mask)
     {
         return detail::char_class_impl<char_type>::isctype(ch, mask);
     }
 
     /// Convert a digit character into the integer it represents.
     ///
     /// \param ch The digit character.
     /// \param radix The radix to use for the conversion.
     /// \pre radix is one of 8, 10, or 16.
     /// \return -1 if ch is not a digit character, the integer value of the character otherwise. If
     ///     char_type is char, std::strtol is used for the conversion. If char_type is wchar_t,
     ///     std::wcstol is used.
     static int value(char_type ch, int radix);
 
     /// No-op
     ///
     locale_type imbue(locale_type loc)
     {
         this->base_type::imbue(*this);
         return loc;
     }
 
     /// No-op
     ///
     static locale_type getloc()
     {
         locale_type loc;
         return loc;
     }
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 // c_regex_traits<>::widen specializations
 /// INTERNAL ONLY
 template<>
 inline char c_regex_traits<char>::widen(char ch)
 {
     return ch;
 }
 
 #ifndef BOOST_XPRESSIVE_NO_WREGEX
 /// INTERNAL ONLY
 template<>
 inline wchar_t c_regex_traits<wchar_t>::widen(char ch)
 {
     using namespace std;
     return btowc(ch);
 }
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////
 // c_regex_traits<>::hash specializations
 /// INTERNAL ONLY
 template<>
 inline unsigned char c_regex_traits<char>::hash(char ch)
 {
     return static_cast<unsigned char>(ch);
 }
 
 #ifndef BOOST_XPRESSIVE_NO_WREGEX
 /// INTERNAL ONLY
 template<>
 inline unsigned char c_regex_traits<wchar_t>::hash(wchar_t ch)
 {
     return static_cast<unsigned char>(ch);
 }
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////
 // c_regex_traits<>::value specializations
 /// INTERNAL ONLY
 template<>
 inline int c_regex_traits<char>::value(char ch, int radix)
 {
     using namespace std;
     BOOST_ASSERT(8 == radix || 10 == radix || 16 == radix);
     char begin[2] = { ch, '\0' }, *end = 0;
     int val = strtol(begin, &end, radix);
     return begin == end ? -1 : val;
 }
 
 #ifndef BOOST_XPRESSIVE_NO_WREGEX
 /// INTERNAL ONLY
 template<>
 inline int c_regex_traits<wchar_t>::value(wchar_t ch, int radix)
 {
     using namespace std;
     BOOST_ASSERT(8 == radix || 10 == radix || 16 == radix);
     wchar_t begin[2] = { ch, L'\0' }, *end = 0;
     int val = wcstol(begin, &end, radix);
     return begin == end ? -1 : val;
 }
 #endif
 
 // Narrow C traits has fold_case() member function.
 template<>
 struct has_fold_case<c_regex_traits<char> >
   : mpl::true_
 {
 };
 
 }}
 
 #endif

This page was automatically generated by the 2.3.7 LXR engine. The LXR team