2.3 KiB
[locale.collate.general]
28 Text processing library [text]
28.3 Localization library [localization]
28.3.4 Standard locale categories [locale.categories]
28.3.4.5 The collate category [category.collate]
28.3.4.5.1 Class template collate [locale.collate]
28.3.4.5.1.1 General [locale.collate.general]
namespace std {templateclass collate : public locale::facet {public:using char_type = charT; using string_type = basic_string; explicit collate(size_t refs = 0); int compare(const charT* low1, const charT* high1, const charT* low2, const charT* high2) const; string_type transform(const charT* low, const charT* high) const; long hash(const charT* low, const charT* high) const; static locale::id id; protected:~collate(); virtual int do_compare(const charT* low1, const charT* high1, const charT* low2, const charT* high2) const; virtual string_type do_transform(const charT* low, const charT* high) const; virtual long do_hash (const charT* low, const charT* high) const; };}
The class collate provides features for use in the collation (comparison) and hashing of strings.
A locale member function template, operator(), uses the collate facet to allow a locale to act directly as the predicate argument for standard algorithms ([algorithms]) and containers operating on strings.
The specializations required in Table 91 ([locale.category]), namely collate and collate<wchar_t>, apply lexicographical ordering ([alg.lex.comparison]).
Each function compares a string of characters *p in the range [low, high).