88#define BOOST_LOCALE_COLLATOR_HPP_INCLUDED
99
1010#include < boost/locale/config.hpp>
11+ #include < boost/locale/detail/facet_id.hpp>
1112#include < locale>
1213
1314#ifdef BOOST_MSVC
@@ -43,17 +44,16 @@ namespace boost { namespace locale {
4344
4445 // / \brief Collation facet.
4546 // /
46- // / It reimplements standard C++ std::collate,
47- // / allowing usage of std::locale for direct string comparison
47+ // / It reimplements standard C++ std::collate with support for collation levels
4848 template <typename CharType>
49- class collator : public std ::collate< CharType> {
49+ class BOOST_SYMBOL_VISIBLE collator : public std::locale::facet, public detail::facet_id<collator< CharType> > {
5050 public:
5151 // / Type of the underlying character
5252 typedef CharType char_type;
5353 // / Type of string used with this facet
5454 typedef std::basic_string<CharType> string_type;
5555
56- // / Compare two strings in rage [b1,e1), [b2,e2) according using a collation level \a level. Calls do_compare
56+ // / Compare two strings in range [b1,e1), [b2,e2) according to collation level \a level. Calls do_compare
5757 // /
5858 // / Returns -1 if the first of the two strings sorts before the seconds, returns 1 if sorts after and 0 if
5959 // / they considered equal.
@@ -66,6 +66,13 @@ namespace boost { namespace locale {
6666 return do_compare (level, b1, e1 , b2, e2 );
6767 }
6868
69+ // / Default compare function as-in std::collate that does not take collation level into account.
70+ // / Uses identical level
71+ int compare (const char_type* b1, const char_type* e1 , const char_type* b2, const char_type* e2 ) const
72+ {
73+ return compare (collate_level::identical, b1, e1 , b2, e2 );
74+ }
75+
6976 // / Create a binary string that can be compared to other in order to get collation order. The string is created
7077 // / for text in range [b,e). It is useful for collation of multiple strings for text.
7178 // /
@@ -80,13 +87,24 @@ namespace boost { namespace locale {
8087 return do_transform (level, b, e);
8188 }
8289
90+ // / Default transform function as-in std::collate that does not take collation level into account.
91+ // / Uses identical level
92+ string_type transform (const char_type* b, const char_type* e) const
93+ {
94+ return transform (collate_level::identical, b, e);
95+ }
96+
8397 // / Calculate a hash of a text in range [b,e). The value can be used for collation sensitive string comparison.
8498 // /
8599 // / If compare(level,b1,e1,b2,e2) == 0 then hash(level,b1,e1) == hash(level,b2,e2)
86100 // /
87101 // / Calls do_hash
88102 long hash (collate_level level, const char_type* b, const char_type* e) const { return do_hash (level, b, e); }
89103
104+ // / Default hash function as-in std::collate that does not take collation level into account.
105+ // / Uses identical level
106+ long hash (const char_type* b, const char_type* e) const { return hash (collate_level::identical, b, e); }
107+
90108 // / Compare two strings \a l and \a r using collation level \a level
91109 // /
92110 // / Returns -1 if the first of the two strings sorts before the seconds, returns 1 if sorts after and 0 if
@@ -107,7 +125,7 @@ namespace boost { namespace locale {
107125 // / Create a binary string from string \a s, that can be compared to other, useful for collation of multiple
108126 // / strings.
109127 // /
110- // / The transformation follows these rules :
128+ // / The transformation follows this rule :
111129 // / \code
112130 // / compare(level,s1,s2) == sign( transform(level,s1).compare(transform(level,s2)) );
113131 // / \endcode
@@ -118,29 +136,7 @@ namespace boost { namespace locale {
118136
119137 protected:
120138 // / constructor of the collator object
121- collator (size_t refs = 0 ) : std::collate<CharType>(refs) {}
122-
123- // / This function is used to override default collation function that does not take in account collation level.
124- // / Uses primary level
125- int
126- do_compare (const char_type* b1, const char_type* e1 , const char_type* b2, const char_type* e2 ) const override
127- {
128- return do_compare (collate_level::identical, b1, e1 , b2, e2 );
129- }
130-
131- // / This function is used to override default collation function that does not take in account collation level.
132- // / Uses primary level
133- string_type do_transform (const char_type* b, const char_type* e) const override
134- {
135- return do_transform (collate_level::identical, b, e);
136- }
137-
138- // / This function is used to override default collation function that does not take in account collation level.
139- // / Uses primary level
140- long do_hash (const char_type* b, const char_type* e) const override
141- {
142- return do_hash (collate_level::identical, b, e);
143- }
139+ collator (size_t refs = 0 ) : std::locale::facet(refs) {}
144140
145141 // / Actual function that performs comparison between the strings. For details see compare member function. Can
146142 // / be overridden.
@@ -157,7 +153,7 @@ namespace boost { namespace locale {
157153 };
158154
159155 // / \brief This class can be used in STL algorithms and containers for comparison of strings
160- // / with a level other than primary
156+ // / with a level other than identical
161157 // /
162158 // / For example:
163159 // /
@@ -169,21 +165,22 @@ namespace boost { namespace locale {
169165 template <typename CharType, collate_level default_level = collate_level::identical>
170166 struct comparator {
171167 public:
172- // / Create a comparator class for locale \a l and with collation leval \a level
168+ // / Create a comparator class for locale \a l and with collation level \a level
173169 // /
174170 // / \throws std::bad_cast: \a l does not have \ref collator facet installed
175171 comparator (const std::locale& l = std::locale(), collate_level level = default_level) :
176- locale_ (l), level_(level)
172+ locale_ (l), collator_(std::use_facet<collator<CharType>>(locale_)), level_(level)
177173 {}
178174
179175 // / Compare two strings -- equivalent to return left < right according to collation rules
180176 bool operator ()(const std::basic_string<CharType>& left, const std::basic_string<CharType>& right) const
181177 {
182- return std::use_facet<collator<CharType>>(locale_) .compare (level_, left, right) < 0 ;
178+ return collator_ .compare (level_, left, right) < 0 ;
183179 }
184180
185181 private:
186182 std::locale locale_;
183+ const collator<CharType>& collator_;
187184 collate_level level_;
188185 };
189186
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