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authormcheshkov <mcheshkov@yandex-team.ru>2022-02-10 16:46:16 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:46:16 +0300
commit1312621288956f199a5bd5342b0133d4395fa725 (patch)
tree1a2c5ffcf89eb53ecd79dbc9bc0a195c27404d0c /contrib/libs/icu/include/unicode/localematcher.h
parente9d19cec64684c9c1e6b0c98297e5b895cf904fe (diff)
downloadydb-1312621288956f199a5bd5342b0133d4395fa725.tar.gz
Restoring authorship annotation for <mcheshkov@yandex-team.ru>. Commit 2 of 2.
Diffstat (limited to 'contrib/libs/icu/include/unicode/localematcher.h')
-rw-r--r--contrib/libs/icu/include/unicode/localematcher.h1330
1 files changed, 665 insertions, 665 deletions
diff --git a/contrib/libs/icu/include/unicode/localematcher.h b/contrib/libs/icu/include/unicode/localematcher.h
index fa97014fb7..2e1a7a349f 100644
--- a/contrib/libs/icu/include/unicode/localematcher.h
+++ b/contrib/libs/icu/include/unicode/localematcher.h
@@ -1,665 +1,665 @@
-// © 2019 and later: Unicode, Inc. and others.
-// License & terms of use: http://www.unicode.org/copyright.html#License
-
-// localematcher.h
-// created: 2019may08 Markus W. Scherer
-
-#ifndef __LOCALEMATCHER_H__
-#define __LOCALEMATCHER_H__
-
-#include "unicode/utypes.h"
-
-#if U_SHOW_CPLUSPLUS_API
-
-#include "unicode/locid.h"
-#include "unicode/stringpiece.h"
-#include "unicode/uobject.h"
-
-/**
- * \file
- * \brief C++ API: Locale matcher: User's desired locales vs. application's supported locales.
- */
-
-#ifndef U_FORCE_HIDE_DRAFT_API
-
-/**
- * Builder option for whether the language subtag or the script subtag is most important.
- *
- * @see Builder#setFavorSubtag(ULocMatchFavorSubtag)
- * @draft ICU 65
- */
-enum ULocMatchFavorSubtag {
- /**
- * Language differences are most important, then script differences, then region differences.
- * (This is the default behavior.)
- *
- * @draft ICU 65
- */
- ULOCMATCH_FAVOR_LANGUAGE,
- /**
- * Makes script differences matter relatively more than language differences.
- *
- * @draft ICU 65
- */
- ULOCMATCH_FAVOR_SCRIPT
-};
-#ifndef U_IN_DOXYGEN
-typedef enum ULocMatchFavorSubtag ULocMatchFavorSubtag;
-#endif
-
-/**
- * Builder option for whether all desired locales are treated equally or
- * earlier ones are preferred.
- *
- * @see Builder#setDemotionPerDesiredLocale(ULocMatchDemotion)
- * @draft ICU 65
- */
-enum ULocMatchDemotion {
- /**
- * All desired locales are treated equally.
- *
- * @draft ICU 65
- */
- ULOCMATCH_DEMOTION_NONE,
- /**
- * Earlier desired locales are preferred.
- *
- * <p>From each desired locale to the next,
- * the distance to any supported locale is increased by an additional amount
- * which is at least as large as most region mismatches.
- * A later desired locale has to have a better match with some supported locale
- * due to more than merely having the same region subtag.
- *
- * <p>For example: <code>Supported={en, sv} desired=[en-GB, sv]</code>
- * yields <code>Result(en-GB, en)</code> because
- * with the demotion of sv its perfect match is no better than
- * the region distance between the earlier desired locale en-GB and en=en-US.
- *
- * <p>Notes:
- * <ul>
- * <li>In some cases, language and/or script differences can be as small as
- * the typical region difference. (Example: sr-Latn vs. sr-Cyrl)
- * <li>It is possible for certain region differences to be larger than usual,
- * and larger than the demotion.
- * (As of CLDR 35 there is no such case, but
- * this is possible in future versions of the data.)
- * </ul>
- *
- * @draft ICU 65
- */
- ULOCMATCH_DEMOTION_REGION
-};
-#ifndef U_IN_DOXYGEN
-typedef enum ULocMatchDemotion ULocMatchDemotion;
-#endif
-
-/**
- * Builder option for whether to include or ignore one-way (fallback) match data.
- * The LocaleMatcher uses CLDR languageMatch data which includes fallback (oneway=true) entries.
- * Sometimes it is desirable to ignore those.
- *
- * <p>For example, consider a web application with the UI in a given language,
- * with a link to another, related web app.
- * The link should include the UI language, and the target server may also use
- * the client’s Accept-Language header data.
- * The target server has its own list of supported languages.
- * One may want to favor UI language consistency, that is,
- * if there is a decent match for the original UI language, we want to use it,
- * but not if it is merely a fallback.
- *
- * @see Builder#setDirection(ULocMatchDirection)
- * @draft ICU 67
- */
-enum ULocMatchDirection {
- /**
- * Locale matching includes one-way matches such as Breton→French. (default)
- *
- * @draft ICU 67
- */
- ULOCMATCH_DIRECTION_WITH_ONE_WAY,
- /**
- * Locale matching limited to two-way matches including e.g. Danish↔Norwegian
- * but ignoring one-way matches.
- *
- * @draft ICU 67
- */
- ULOCMATCH_DIRECTION_ONLY_TWO_WAY
-};
-#ifndef U_IN_DOXYGEN
-typedef enum ULocMatchDirection ULocMatchDirection;
-#endif
-
-struct UHashtable;
-
-U_NAMESPACE_BEGIN
-
-struct LSR;
-
-class LocaleDistance;
-class LocaleLsrIterator;
-class UVector;
-class XLikelySubtags;
-
-/**
- * Immutable class that picks the best match between a user's desired locales and
- * an application's supported locales.
- * Movable but not copyable.
- *
- * <p>Example:
- * <pre>
- * UErrorCode errorCode = U_ZERO_ERROR;
- * LocaleMatcher matcher = LocaleMatcher::Builder().setSupportedLocales("fr, en-GB, en").build(errorCode);
- * Locale *bestSupported = matcher.getBestLocale(Locale.US, errorCode); // "en"
- * </pre>
- *
- * <p>A matcher takes into account when languages are close to one another,
- * such as Danish and Norwegian,
- * and when regional variants are close, like en-GB and en-AU as opposed to en-US.
- *
- * <p>If there are multiple supported locales with the same (language, script, region)
- * likely subtags, then the current implementation returns the first of those locales.
- * It ignores variant subtags (except for pseudolocale variants) and extensions.
- * This may change in future versions.
- *
- * <p>For example, the current implementation does not distinguish between
- * de, de-DE, de-Latn, de-1901, de-u-co-phonebk.
- *
- * <p>If you prefer one equivalent locale over another, then provide only the preferred one,
- * or place it earlier in the list of supported locales.
- *
- * <p>Otherwise, the order of supported locales may have no effect on the best-match results.
- * The current implementation compares each desired locale with supported locales
- * in the following order:
- * 1. Default locale, if supported;
- * 2. CLDR "paradigm locales" like en-GB and es-419;
- * 3. other supported locales.
- * This may change in future versions.
- *
- * <p>Often a product will just need one matcher instance, built with the languages
- * that it supports. However, it may want multiple instances with different
- * default languages based on additional information, such as the domain.
- *
- * <p>This class is not intended for public subclassing.
- *
- * @draft ICU 65
- */
-class U_COMMON_API LocaleMatcher : public UMemory {
-public:
- /**
- * Data for the best-matching pair of a desired and a supported locale.
- * Movable but not copyable.
- *
- * @draft ICU 65
- */
- class U_COMMON_API Result : public UMemory {
- public:
- /**
- * Move constructor; might modify the source.
- * This object will have the same contents that the source object had.
- *
- * @param src Result to move contents from.
- * @draft ICU 65
- */
- Result(Result &&src) U_NOEXCEPT;
-
- /**
- * Destructor.
- *
- * @draft ICU 65
- */
- ~Result();
-
- /**
- * Move assignment; might modify the source.
- * This object will have the same contents that the source object had.
- *
- * @param src Result to move contents from.
- * @draft ICU 65
- */
- Result &operator=(Result &&src) U_NOEXCEPT;
-
-#ifndef U_HIDE_DRAFT_API
- /**
- * Returns the best-matching desired locale.
- * nullptr if the list of desired locales is empty or if none matched well enough.
- *
- * @return the best-matching desired locale, or nullptr.
- * @draft ICU 65
- */
- inline const Locale *getDesiredLocale() const { return desiredLocale; }
-
- /**
- * Returns the best-matching supported locale.
- * If none matched well enough, this is the default locale.
- * The default locale is nullptr if the list of supported locales is empty and
- * no explicit default locale is set.
- *
- * @return the best-matching supported locale, or nullptr.
- * @draft ICU 65
- */
- inline const Locale *getSupportedLocale() const { return supportedLocale; }
-
- /**
- * Returns the index of the best-matching desired locale in the input Iterable order.
- * -1 if the list of desired locales is empty or if none matched well enough.
- *
- * @return the index of the best-matching desired locale, or -1.
- * @draft ICU 65
- */
- inline int32_t getDesiredIndex() const { return desiredIndex; }
-
- /**
- * Returns the index of the best-matching supported locale in the
- * constructor’s or builder’s input order (“set” Collection plus “added” locales).
- * If the matcher was built from a locale list string, then the iteration order is that
- * of a LocalePriorityList built from the same string.
- * -1 if the list of supported locales is empty or if none matched well enough.
- *
- * @return the index of the best-matching supported locale, or -1.
- * @draft ICU 65
- */
- inline int32_t getSupportedIndex() const { return supportedIndex; }
-
- /**
- * Takes the best-matching supported locale and adds relevant fields of the
- * best-matching desired locale, such as the -t- and -u- extensions.
- * May replace some fields of the supported locale.
- * The result is the locale that should be used for date and number formatting, collation, etc.
- * Returns the root locale if getSupportedLocale() returns nullptr.
- *
- * <p>Example: desired=ar-SA-u-nu-latn, supported=ar-EG, resolved locale=ar-SA-u-nu-latn
- *
- * @return a locale combining the best-matching desired and supported locales.
- * @draft ICU 65
- */
- Locale makeResolvedLocale(UErrorCode &errorCode) const;
-#endif // U_HIDE_DRAFT_API
-
- private:
- Result(const Locale *desired, const Locale *supported,
- int32_t desIndex, int32_t suppIndex, UBool owned) :
- desiredLocale(desired), supportedLocale(supported),
- desiredIndex(desIndex), supportedIndex(suppIndex),
- desiredIsOwned(owned) {}
-
- Result(const Result &other) = delete;
- Result &operator=(const Result &other) = delete;
-
- const Locale *desiredLocale;
- const Locale *supportedLocale;
- int32_t desiredIndex;
- int32_t supportedIndex;
- UBool desiredIsOwned;
-
- friend class LocaleMatcher;
- };
-
- /**
- * LocaleMatcher builder.
- * Movable but not copyable.
- *
- * @see LocaleMatcher#builder()
- * @draft ICU 65
- */
- class U_COMMON_API Builder : public UMemory {
- public:
- /**
- * Constructs a builder used in chaining parameters for building a LocaleMatcher.
- *
- * @return a new Builder object
- * @draft ICU 65
- */
- Builder() {}
-
- /**
- * Move constructor; might modify the source.
- * This builder will have the same contents that the source builder had.
- *
- * @param src Builder to move contents from.
- * @draft ICU 65
- */
- Builder(Builder &&src) U_NOEXCEPT;
-
- /**
- * Destructor.
- *
- * @draft ICU 65
- */
- ~Builder();
-
- /**
- * Move assignment; might modify the source.
- * This builder will have the same contents that the source builder had.
- *
- * @param src Builder to move contents from.
- * @draft ICU 65
- */
- Builder &operator=(Builder &&src) U_NOEXCEPT;
-
-#ifndef U_HIDE_DRAFT_API
- /**
- * Parses an Accept-Language string
- * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
- * such as "af, en, fr;q=0.9", and sets the supported locales accordingly.
- * Allows whitespace in more places but does not allow "*".
- * Clears any previously set/added supported locales first.
- *
- * @param locales the Accept-Language string of locales to set
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &setSupportedLocalesFromListString(StringPiece locales);
-
- /**
- * Copies the supported locales, preserving iteration order.
- * Clears any previously set/added supported locales first.
- * Duplicates are allowed, and are not removed.
- *
- * @param locales the list of locale
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &setSupportedLocales(Locale::Iterator &locales);
-
- /**
- * Copies the supported locales from the begin/end range, preserving iteration order.
- * Clears any previously set/added supported locales first.
- * Duplicates are allowed, and are not removed.
- *
- * Each of the iterator parameter values must be an
- * input iterator whose value is convertible to const Locale &.
- *
- * @param begin Start of range.
- * @param end Exclusive end of range.
- * @return this Builder object
- * @draft ICU 65
- */
- template<typename Iter>
- Builder &setSupportedLocales(Iter begin, Iter end) {
- if (U_FAILURE(errorCode_)) { return *this; }
- clearSupportedLocales();
- while (begin != end) {
- addSupportedLocale(*begin++);
- }
- return *this;
- }
-
- /**
- * Copies the supported locales from the begin/end range, preserving iteration order.
- * Calls the converter to convert each *begin to a Locale or const Locale &.
- * Clears any previously set/added supported locales first.
- * Duplicates are allowed, and are not removed.
- *
- * Each of the iterator parameter values must be an
- * input iterator whose value is convertible to const Locale &.
- *
- * @param begin Start of range.
- * @param end Exclusive end of range.
- * @param converter Converter from *begin to const Locale & or compatible.
- * @return this Builder object
- * @draft ICU 65
- */
- template<typename Iter, typename Conv>
- Builder &setSupportedLocalesViaConverter(Iter begin, Iter end, Conv converter) {
- if (U_FAILURE(errorCode_)) { return *this; }
- clearSupportedLocales();
- while (begin != end) {
- addSupportedLocale(converter(*begin++));
- }
- return *this;
- }
-
- /**
- * Adds another supported locale.
- * Duplicates are allowed, and are not removed.
- *
- * @param locale another locale
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &addSupportedLocale(const Locale &locale);
-
- /**
- * Sets the default locale; if nullptr, or if it is not set explicitly,
- * then the first supported locale is used as the default locale.
- *
- * @param defaultLocale the default locale (will be copied)
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &setDefaultLocale(const Locale *defaultLocale);
-
- /**
- * If ULOCMATCH_FAVOR_SCRIPT, then the language differences are smaller than script
- * differences.
- * This is used in situations (such as maps) where
- * it is better to fall back to the same script than a similar language.
- *
- * @param subtag the subtag to favor
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &setFavorSubtag(ULocMatchFavorSubtag subtag);
-
- /**
- * Option for whether all desired locales are treated equally or
- * earlier ones are preferred (this is the default).
- *
- * @param demotion the demotion per desired locale to set.
- * @return this Builder object
- * @draft ICU 65
- */
- Builder &setDemotionPerDesiredLocale(ULocMatchDemotion demotion);
-
- /**
- * Option for whether to include or ignore one-way (fallback) match data.
- * By default, they are included.
- *
- * @param direction the match direction to set.
- * @return this Builder object
- * @draft ICU 67
- */
- Builder &setDirection(ULocMatchDirection direction) {
- if (U_SUCCESS(errorCode_)) {
- direction_ = direction;
- }
- return *this;
- }
-
- /**
- * Sets the UErrorCode if an error occurred while setting parameters.
- * Preserves older error codes in the outErrorCode.
- *
- * @param outErrorCode Set to an error code if it does not contain one already
- * and an error occurred while setting parameters.
- * Otherwise unchanged.
- * @return TRUE if U_FAILURE(outErrorCode)
- * @draft ICU 65
- */
- UBool copyErrorTo(UErrorCode &outErrorCode) const;
-
- /**
- * Builds and returns a new locale matcher.
- * This builder can continue to be used.
- *
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return new LocaleMatcher.
- * @draft ICU 65
- */
- LocaleMatcher build(UErrorCode &errorCode) const;
-#endif // U_HIDE_DRAFT_API
-
- private:
- friend class LocaleMatcher;
-
- Builder(const Builder &other) = delete;
- Builder &operator=(const Builder &other) = delete;
-
- void clearSupportedLocales();
- bool ensureSupportedLocaleVector();
-
- UErrorCode errorCode_ = U_ZERO_ERROR;
- UVector *supportedLocales_ = nullptr;
- int32_t thresholdDistance_ = -1;
- ULocMatchDemotion demotion_ = ULOCMATCH_DEMOTION_REGION;
- Locale *defaultLocale_ = nullptr;
- ULocMatchFavorSubtag favor_ = ULOCMATCH_FAVOR_LANGUAGE;
- ULocMatchDirection direction_ = ULOCMATCH_DIRECTION_WITH_ONE_WAY;
- };
-
- // FYI No public LocaleMatcher constructors in C++; use the Builder.
-
- /**
- * Move copy constructor; might modify the source.
- * This matcher will have the same settings that the source matcher had.
- * @param src source matcher
- * @draft ICU 65
- */
- LocaleMatcher(LocaleMatcher &&src) U_NOEXCEPT;
-
- /**
- * Destructor.
- * @draft ICU 65
- */
- ~LocaleMatcher();
-
- /**
- * Move assignment operator; might modify the source.
- * This matcher will have the same settings that the source matcher had.
- * The behavior is undefined if *this and src are the same object.
- * @param src source matcher
- * @return *this
- * @draft ICU 65
- */
- LocaleMatcher &operator=(LocaleMatcher &&src) U_NOEXCEPT;
-
-#ifndef U_HIDE_DRAFT_API
- /**
- * Returns the supported locale which best matches the desired locale.
- *
- * @param desiredLocale Typically a user's language.
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return the best-matching supported locale.
- * @draft ICU 65
- */
- const Locale *getBestMatch(const Locale &desiredLocale, UErrorCode &errorCode) const;
-
- /**
- * Returns the supported locale which best matches one of the desired locales.
- *
- * @param desiredLocales Typically a user's languages, in order of preference (descending).
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return the best-matching supported locale.
- * @draft ICU 65
- */
- const Locale *getBestMatch(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
-
- /**
- * Parses an Accept-Language string
- * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
- * such as "af, en, fr;q=0.9",
- * and returns the supported locale which best matches one of the desired locales.
- * Allows whitespace in more places but does not allow "*".
- *
- * @param desiredLocaleList Typically a user's languages, as an Accept-Language string.
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return the best-matching supported locale.
- * @draft ICU 65
- */
- const Locale *getBestMatchForListString(StringPiece desiredLocaleList, UErrorCode &errorCode) const;
-
- /**
- * Returns the best match between the desired locale and the supported locales.
- * If the result's desired locale is not nullptr, then it is the address of the input locale.
- * It has not been cloned.
- *
- * @param desiredLocale Typically a user's language.
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return the best-matching pair of the desired and a supported locale.
- * @draft ICU 65
- */
- Result getBestMatchResult(const Locale &desiredLocale, UErrorCode &errorCode) const;
-
- /**
- * Returns the best match between the desired and supported locales.
- * If the result's desired locale is not nullptr, then it is a clone of
- * the best-matching desired locale. The Result object owns the clone.
- *
- * @param desiredLocales Typically a user's languages, in order of preference (descending).
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return the best-matching pair of a desired and a supported locale.
- * @draft ICU 65
- */
- Result getBestMatchResult(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
-#endif // U_HIDE_DRAFT_API
-
-#ifndef U_HIDE_INTERNAL_API
- /**
- * Returns a fraction between 0 and 1, where 1 means that the languages are a
- * perfect match, and 0 means that they are completely different.
- *
- * <p>This is mostly an implementation detail, and the precise values may change over time.
- * The implementation may use either the maximized forms or the others ones, or both.
- * The implementation may or may not rely on the forms to be consistent with each other.
- *
- * <p>Callers should construct and use a matcher rather than match pairs of locales directly.
- *
- * @param desired Desired locale.
- * @param supported Supported locale.
- * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
- * or else the function returns immediately. Check for U_FAILURE()
- * on output or use with function chaining. (See User Guide for details.)
- * @return value between 0 and 1, inclusive.
- * @internal (has a known user)
- */
- double internalMatch(const Locale &desired, const Locale &supported, UErrorCode &errorCode) const;
-#endif // U_HIDE_INTERNAL_API
-
-private:
- LocaleMatcher(const Builder &builder, UErrorCode &errorCode);
- LocaleMatcher(const LocaleMatcher &other) = delete;
- LocaleMatcher &operator=(const LocaleMatcher &other) = delete;
-
- int32_t putIfAbsent(const LSR &lsr, int32_t i, int32_t suppLength, UErrorCode &errorCode);
-
- int32_t getBestSuppIndex(LSR desiredLSR, LocaleLsrIterator *remainingIter, UErrorCode &errorCode) const;
-
- const XLikelySubtags &likelySubtags;
- const LocaleDistance &localeDistance;
- int32_t thresholdDistance;
- int32_t demotionPerDesiredLocale;
- ULocMatchFavorSubtag favorSubtag;
- ULocMatchDirection direction;
-
- // These are in input order.
- const Locale ** supportedLocales;
- LSR *lsrs;
- int32_t supportedLocalesLength;
- // These are in preference order: 1. Default locale 2. paradigm locales 3. others.
- UHashtable *supportedLsrToIndex; // Map<LSR, Integer> stores index+1 because 0 is "not found"
- // Array versions of the supportedLsrToIndex keys and values.
- // The distance lookup loops over the supportedLSRs and returns the index of the best match.
- const LSR **supportedLSRs;
- int32_t *supportedIndexes;
- int32_t supportedLSRsLength;
- Locale *ownedDefaultLocale;
- const Locale *defaultLocale;
-};
-
-U_NAMESPACE_END
-
-#endif // U_FORCE_HIDE_DRAFT_API
-#endif // U_SHOW_CPLUSPLUS_API
-#endif // __LOCALEMATCHER_H__
+// © 2019 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html#License
+
+// localematcher.h
+// created: 2019may08 Markus W. Scherer
+
+#ifndef __LOCALEMATCHER_H__
+#define __LOCALEMATCHER_H__
+
+#include "unicode/utypes.h"
+
+#if U_SHOW_CPLUSPLUS_API
+
+#include "unicode/locid.h"
+#include "unicode/stringpiece.h"
+#include "unicode/uobject.h"
+
+/**
+ * \file
+ * \brief C++ API: Locale matcher: User's desired locales vs. application's supported locales.
+ */
+
+#ifndef U_FORCE_HIDE_DRAFT_API
+
+/**
+ * Builder option for whether the language subtag or the script subtag is most important.
+ *
+ * @see Builder#setFavorSubtag(ULocMatchFavorSubtag)
+ * @draft ICU 65
+ */
+enum ULocMatchFavorSubtag {
+ /**
+ * Language differences are most important, then script differences, then region differences.
+ * (This is the default behavior.)
+ *
+ * @draft ICU 65
+ */
+ ULOCMATCH_FAVOR_LANGUAGE,
+ /**
+ * Makes script differences matter relatively more than language differences.
+ *
+ * @draft ICU 65
+ */
+ ULOCMATCH_FAVOR_SCRIPT
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchFavorSubtag ULocMatchFavorSubtag;
+#endif
+
+/**
+ * Builder option for whether all desired locales are treated equally or
+ * earlier ones are preferred.
+ *
+ * @see Builder#setDemotionPerDesiredLocale(ULocMatchDemotion)
+ * @draft ICU 65
+ */
+enum ULocMatchDemotion {
+ /**
+ * All desired locales are treated equally.
+ *
+ * @draft ICU 65
+ */
+ ULOCMATCH_DEMOTION_NONE,
+ /**
+ * Earlier desired locales are preferred.
+ *
+ * <p>From each desired locale to the next,
+ * the distance to any supported locale is increased by an additional amount
+ * which is at least as large as most region mismatches.
+ * A later desired locale has to have a better match with some supported locale
+ * due to more than merely having the same region subtag.
+ *
+ * <p>For example: <code>Supported={en, sv} desired=[en-GB, sv]</code>
+ * yields <code>Result(en-GB, en)</code> because
+ * with the demotion of sv its perfect match is no better than
+ * the region distance between the earlier desired locale en-GB and en=en-US.
+ *
+ * <p>Notes:
+ * <ul>
+ * <li>In some cases, language and/or script differences can be as small as
+ * the typical region difference. (Example: sr-Latn vs. sr-Cyrl)
+ * <li>It is possible for certain region differences to be larger than usual,
+ * and larger than the demotion.
+ * (As of CLDR 35 there is no such case, but
+ * this is possible in future versions of the data.)
+ * </ul>
+ *
+ * @draft ICU 65
+ */
+ ULOCMATCH_DEMOTION_REGION
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchDemotion ULocMatchDemotion;
+#endif
+
+/**
+ * Builder option for whether to include or ignore one-way (fallback) match data.
+ * The LocaleMatcher uses CLDR languageMatch data which includes fallback (oneway=true) entries.
+ * Sometimes it is desirable to ignore those.
+ *
+ * <p>For example, consider a web application with the UI in a given language,
+ * with a link to another, related web app.
+ * The link should include the UI language, and the target server may also use
+ * the client’s Accept-Language header data.
+ * The target server has its own list of supported languages.
+ * One may want to favor UI language consistency, that is,
+ * if there is a decent match for the original UI language, we want to use it,
+ * but not if it is merely a fallback.
+ *
+ * @see Builder#setDirection(ULocMatchDirection)
+ * @draft ICU 67
+ */
+enum ULocMatchDirection {
+ /**
+ * Locale matching includes one-way matches such as Breton→French. (default)
+ *
+ * @draft ICU 67
+ */
+ ULOCMATCH_DIRECTION_WITH_ONE_WAY,
+ /**
+ * Locale matching limited to two-way matches including e.g. Danish↔Norwegian
+ * but ignoring one-way matches.
+ *
+ * @draft ICU 67
+ */
+ ULOCMATCH_DIRECTION_ONLY_TWO_WAY
+};
+#ifndef U_IN_DOXYGEN
+typedef enum ULocMatchDirection ULocMatchDirection;
+#endif
+
+struct UHashtable;
+
+U_NAMESPACE_BEGIN
+
+struct LSR;
+
+class LocaleDistance;
+class LocaleLsrIterator;
+class UVector;
+class XLikelySubtags;
+
+/**
+ * Immutable class that picks the best match between a user's desired locales and
+ * an application's supported locales.
+ * Movable but not copyable.
+ *
+ * <p>Example:
+ * <pre>
+ * UErrorCode errorCode = U_ZERO_ERROR;
+ * LocaleMatcher matcher = LocaleMatcher::Builder().setSupportedLocales("fr, en-GB, en").build(errorCode);
+ * Locale *bestSupported = matcher.getBestLocale(Locale.US, errorCode); // "en"
+ * </pre>
+ *
+ * <p>A matcher takes into account when languages are close to one another,
+ * such as Danish and Norwegian,
+ * and when regional variants are close, like en-GB and en-AU as opposed to en-US.
+ *
+ * <p>If there are multiple supported locales with the same (language, script, region)
+ * likely subtags, then the current implementation returns the first of those locales.
+ * It ignores variant subtags (except for pseudolocale variants) and extensions.
+ * This may change in future versions.
+ *
+ * <p>For example, the current implementation does not distinguish between
+ * de, de-DE, de-Latn, de-1901, de-u-co-phonebk.
+ *
+ * <p>If you prefer one equivalent locale over another, then provide only the preferred one,
+ * or place it earlier in the list of supported locales.
+ *
+ * <p>Otherwise, the order of supported locales may have no effect on the best-match results.
+ * The current implementation compares each desired locale with supported locales
+ * in the following order:
+ * 1. Default locale, if supported;
+ * 2. CLDR "paradigm locales" like en-GB and es-419;
+ * 3. other supported locales.
+ * This may change in future versions.
+ *
+ * <p>Often a product will just need one matcher instance, built with the languages
+ * that it supports. However, it may want multiple instances with different
+ * default languages based on additional information, such as the domain.
+ *
+ * <p>This class is not intended for public subclassing.
+ *
+ * @draft ICU 65
+ */
+class U_COMMON_API LocaleMatcher : public UMemory {
+public:
+ /**
+ * Data for the best-matching pair of a desired and a supported locale.
+ * Movable but not copyable.
+ *
+ * @draft ICU 65
+ */
+ class U_COMMON_API Result : public UMemory {
+ public:
+ /**
+ * Move constructor; might modify the source.
+ * This object will have the same contents that the source object had.
+ *
+ * @param src Result to move contents from.
+ * @draft ICU 65
+ */
+ Result(Result &&src) U_NOEXCEPT;
+
+ /**
+ * Destructor.
+ *
+ * @draft ICU 65
+ */
+ ~Result();
+
+ /**
+ * Move assignment; might modify the source.
+ * This object will have the same contents that the source object had.
+ *
+ * @param src Result to move contents from.
+ * @draft ICU 65
+ */
+ Result &operator=(Result &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+ /**
+ * Returns the best-matching desired locale.
+ * nullptr if the list of desired locales is empty or if none matched well enough.
+ *
+ * @return the best-matching desired locale, or nullptr.
+ * @draft ICU 65
+ */
+ inline const Locale *getDesiredLocale() const { return desiredLocale; }
+
+ /**
+ * Returns the best-matching supported locale.
+ * If none matched well enough, this is the default locale.
+ * The default locale is nullptr if the list of supported locales is empty and
+ * no explicit default locale is set.
+ *
+ * @return the best-matching supported locale, or nullptr.
+ * @draft ICU 65
+ */
+ inline const Locale *getSupportedLocale() const { return supportedLocale; }
+
+ /**
+ * Returns the index of the best-matching desired locale in the input Iterable order.
+ * -1 if the list of desired locales is empty or if none matched well enough.
+ *
+ * @return the index of the best-matching desired locale, or -1.
+ * @draft ICU 65
+ */
+ inline int32_t getDesiredIndex() const { return desiredIndex; }
+
+ /**
+ * Returns the index of the best-matching supported locale in the
+ * constructor’s or builder’s input order (“set” Collection plus “added” locales).
+ * If the matcher was built from a locale list string, then the iteration order is that
+ * of a LocalePriorityList built from the same string.
+ * -1 if the list of supported locales is empty or if none matched well enough.
+ *
+ * @return the index of the best-matching supported locale, or -1.
+ * @draft ICU 65
+ */
+ inline int32_t getSupportedIndex() const { return supportedIndex; }
+
+ /**
+ * Takes the best-matching supported locale and adds relevant fields of the
+ * best-matching desired locale, such as the -t- and -u- extensions.
+ * May replace some fields of the supported locale.
+ * The result is the locale that should be used for date and number formatting, collation, etc.
+ * Returns the root locale if getSupportedLocale() returns nullptr.
+ *
+ * <p>Example: desired=ar-SA-u-nu-latn, supported=ar-EG, resolved locale=ar-SA-u-nu-latn
+ *
+ * @return a locale combining the best-matching desired and supported locales.
+ * @draft ICU 65
+ */
+ Locale makeResolvedLocale(UErrorCode &errorCode) const;
+#endif // U_HIDE_DRAFT_API
+
+ private:
+ Result(const Locale *desired, const Locale *supported,
+ int32_t desIndex, int32_t suppIndex, UBool owned) :
+ desiredLocale(desired), supportedLocale(supported),
+ desiredIndex(desIndex), supportedIndex(suppIndex),
+ desiredIsOwned(owned) {}
+
+ Result(const Result &other) = delete;
+ Result &operator=(const Result &other) = delete;
+
+ const Locale *desiredLocale;
+ const Locale *supportedLocale;
+ int32_t desiredIndex;
+ int32_t supportedIndex;
+ UBool desiredIsOwned;
+
+ friend class LocaleMatcher;
+ };
+
+ /**
+ * LocaleMatcher builder.
+ * Movable but not copyable.
+ *
+ * @see LocaleMatcher#builder()
+ * @draft ICU 65
+ */
+ class U_COMMON_API Builder : public UMemory {
+ public:
+ /**
+ * Constructs a builder used in chaining parameters for building a LocaleMatcher.
+ *
+ * @return a new Builder object
+ * @draft ICU 65
+ */
+ Builder() {}
+
+ /**
+ * Move constructor; might modify the source.
+ * This builder will have the same contents that the source builder had.
+ *
+ * @param src Builder to move contents from.
+ * @draft ICU 65
+ */
+ Builder(Builder &&src) U_NOEXCEPT;
+
+ /**
+ * Destructor.
+ *
+ * @draft ICU 65
+ */
+ ~Builder();
+
+ /**
+ * Move assignment; might modify the source.
+ * This builder will have the same contents that the source builder had.
+ *
+ * @param src Builder to move contents from.
+ * @draft ICU 65
+ */
+ Builder &operator=(Builder &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+ /**
+ * Parses an Accept-Language string
+ * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
+ * such as "af, en, fr;q=0.9", and sets the supported locales accordingly.
+ * Allows whitespace in more places but does not allow "*".
+ * Clears any previously set/added supported locales first.
+ *
+ * @param locales the Accept-Language string of locales to set
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &setSupportedLocalesFromListString(StringPiece locales);
+
+ /**
+ * Copies the supported locales, preserving iteration order.
+ * Clears any previously set/added supported locales first.
+ * Duplicates are allowed, and are not removed.
+ *
+ * @param locales the list of locale
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &setSupportedLocales(Locale::Iterator &locales);
+
+ /**
+ * Copies the supported locales from the begin/end range, preserving iteration order.
+ * Clears any previously set/added supported locales first.
+ * Duplicates are allowed, and are not removed.
+ *
+ * Each of the iterator parameter values must be an
+ * input iterator whose value is convertible to const Locale &.
+ *
+ * @param begin Start of range.
+ * @param end Exclusive end of range.
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ template<typename Iter>
+ Builder &setSupportedLocales(Iter begin, Iter end) {
+ if (U_FAILURE(errorCode_)) { return *this; }
+ clearSupportedLocales();
+ while (begin != end) {
+ addSupportedLocale(*begin++);
+ }
+ return *this;
+ }
+
+ /**
+ * Copies the supported locales from the begin/end range, preserving iteration order.
+ * Calls the converter to convert each *begin to a Locale or const Locale &.
+ * Clears any previously set/added supported locales first.
+ * Duplicates are allowed, and are not removed.
+ *
+ * Each of the iterator parameter values must be an
+ * input iterator whose value is convertible to const Locale &.
+ *
+ * @param begin Start of range.
+ * @param end Exclusive end of range.
+ * @param converter Converter from *begin to const Locale & or compatible.
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ template<typename Iter, typename Conv>
+ Builder &setSupportedLocalesViaConverter(Iter begin, Iter end, Conv converter) {
+ if (U_FAILURE(errorCode_)) { return *this; }
+ clearSupportedLocales();
+ while (begin != end) {
+ addSupportedLocale(converter(*begin++));
+ }
+ return *this;
+ }
+
+ /**
+ * Adds another supported locale.
+ * Duplicates are allowed, and are not removed.
+ *
+ * @param locale another locale
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &addSupportedLocale(const Locale &locale);
+
+ /**
+ * Sets the default locale; if nullptr, or if it is not set explicitly,
+ * then the first supported locale is used as the default locale.
+ *
+ * @param defaultLocale the default locale (will be copied)
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &setDefaultLocale(const Locale *defaultLocale);
+
+ /**
+ * If ULOCMATCH_FAVOR_SCRIPT, then the language differences are smaller than script
+ * differences.
+ * This is used in situations (such as maps) where
+ * it is better to fall back to the same script than a similar language.
+ *
+ * @param subtag the subtag to favor
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &setFavorSubtag(ULocMatchFavorSubtag subtag);
+
+ /**
+ * Option for whether all desired locales are treated equally or
+ * earlier ones are preferred (this is the default).
+ *
+ * @param demotion the demotion per desired locale to set.
+ * @return this Builder object
+ * @draft ICU 65
+ */
+ Builder &setDemotionPerDesiredLocale(ULocMatchDemotion demotion);
+
+ /**
+ * Option for whether to include or ignore one-way (fallback) match data.
+ * By default, they are included.
+ *
+ * @param direction the match direction to set.
+ * @return this Builder object
+ * @draft ICU 67
+ */
+ Builder &setDirection(ULocMatchDirection direction) {
+ if (U_SUCCESS(errorCode_)) {
+ direction_ = direction;
+ }
+ return *this;
+ }
+
+ /**
+ * Sets the UErrorCode if an error occurred while setting parameters.
+ * Preserves older error codes in the outErrorCode.
+ *
+ * @param outErrorCode Set to an error code if it does not contain one already
+ * and an error occurred while setting parameters.
+ * Otherwise unchanged.
+ * @return TRUE if U_FAILURE(outErrorCode)
+ * @draft ICU 65
+ */
+ UBool copyErrorTo(UErrorCode &outErrorCode) const;
+
+ /**
+ * Builds and returns a new locale matcher.
+ * This builder can continue to be used.
+ *
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return new LocaleMatcher.
+ * @draft ICU 65
+ */
+ LocaleMatcher build(UErrorCode &errorCode) const;
+#endif // U_HIDE_DRAFT_API
+
+ private:
+ friend class LocaleMatcher;
+
+ Builder(const Builder &other) = delete;
+ Builder &operator=(const Builder &other) = delete;
+
+ void clearSupportedLocales();
+ bool ensureSupportedLocaleVector();
+
+ UErrorCode errorCode_ = U_ZERO_ERROR;
+ UVector *supportedLocales_ = nullptr;
+ int32_t thresholdDistance_ = -1;
+ ULocMatchDemotion demotion_ = ULOCMATCH_DEMOTION_REGION;
+ Locale *defaultLocale_ = nullptr;
+ ULocMatchFavorSubtag favor_ = ULOCMATCH_FAVOR_LANGUAGE;
+ ULocMatchDirection direction_ = ULOCMATCH_DIRECTION_WITH_ONE_WAY;
+ };
+
+ // FYI No public LocaleMatcher constructors in C++; use the Builder.
+
+ /**
+ * Move copy constructor; might modify the source.
+ * This matcher will have the same settings that the source matcher had.
+ * @param src source matcher
+ * @draft ICU 65
+ */
+ LocaleMatcher(LocaleMatcher &&src) U_NOEXCEPT;
+
+ /**
+ * Destructor.
+ * @draft ICU 65
+ */
+ ~LocaleMatcher();
+
+ /**
+ * Move assignment operator; might modify the source.
+ * This matcher will have the same settings that the source matcher had.
+ * The behavior is undefined if *this and src are the same object.
+ * @param src source matcher
+ * @return *this
+ * @draft ICU 65
+ */
+ LocaleMatcher &operator=(LocaleMatcher &&src) U_NOEXCEPT;
+
+#ifndef U_HIDE_DRAFT_API
+ /**
+ * Returns the supported locale which best matches the desired locale.
+ *
+ * @param desiredLocale Typically a user's language.
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return the best-matching supported locale.
+ * @draft ICU 65
+ */
+ const Locale *getBestMatch(const Locale &desiredLocale, UErrorCode &errorCode) const;
+
+ /**
+ * Returns the supported locale which best matches one of the desired locales.
+ *
+ * @param desiredLocales Typically a user's languages, in order of preference (descending).
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return the best-matching supported locale.
+ * @draft ICU 65
+ */
+ const Locale *getBestMatch(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
+
+ /**
+ * Parses an Accept-Language string
+ * (<a href="https://tools.ietf.org/html/rfc2616#section-14.4">RFC 2616 Section 14.4</a>),
+ * such as "af, en, fr;q=0.9",
+ * and returns the supported locale which best matches one of the desired locales.
+ * Allows whitespace in more places but does not allow "*".
+ *
+ * @param desiredLocaleList Typically a user's languages, as an Accept-Language string.
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return the best-matching supported locale.
+ * @draft ICU 65
+ */
+ const Locale *getBestMatchForListString(StringPiece desiredLocaleList, UErrorCode &errorCode) const;
+
+ /**
+ * Returns the best match between the desired locale and the supported locales.
+ * If the result's desired locale is not nullptr, then it is the address of the input locale.
+ * It has not been cloned.
+ *
+ * @param desiredLocale Typically a user's language.
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return the best-matching pair of the desired and a supported locale.
+ * @draft ICU 65
+ */
+ Result getBestMatchResult(const Locale &desiredLocale, UErrorCode &errorCode) const;
+
+ /**
+ * Returns the best match between the desired and supported locales.
+ * If the result's desired locale is not nullptr, then it is a clone of
+ * the best-matching desired locale. The Result object owns the clone.
+ *
+ * @param desiredLocales Typically a user's languages, in order of preference (descending).
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return the best-matching pair of a desired and a supported locale.
+ * @draft ICU 65
+ */
+ Result getBestMatchResult(Locale::Iterator &desiredLocales, UErrorCode &errorCode) const;
+#endif // U_HIDE_DRAFT_API
+
+#ifndef U_HIDE_INTERNAL_API
+ /**
+ * Returns a fraction between 0 and 1, where 1 means that the languages are a
+ * perfect match, and 0 means that they are completely different.
+ *
+ * <p>This is mostly an implementation detail, and the precise values may change over time.
+ * The implementation may use either the maximized forms or the others ones, or both.
+ * The implementation may or may not rely on the forms to be consistent with each other.
+ *
+ * <p>Callers should construct and use a matcher rather than match pairs of locales directly.
+ *
+ * @param desired Desired locale.
+ * @param supported Supported locale.
+ * @param errorCode ICU error code. Its input value must pass the U_SUCCESS() test,
+ * or else the function returns immediately. Check for U_FAILURE()
+ * on output or use with function chaining. (See User Guide for details.)
+ * @return value between 0 and 1, inclusive.
+ * @internal (has a known user)
+ */
+ double internalMatch(const Locale &desired, const Locale &supported, UErrorCode &errorCode) const;
+#endif // U_HIDE_INTERNAL_API
+
+private:
+ LocaleMatcher(const Builder &builder, UErrorCode &errorCode);
+ LocaleMatcher(const LocaleMatcher &other) = delete;
+ LocaleMatcher &operator=(const LocaleMatcher &other) = delete;
+
+ int32_t putIfAbsent(const LSR &lsr, int32_t i, int32_t suppLength, UErrorCode &errorCode);
+
+ int32_t getBestSuppIndex(LSR desiredLSR, LocaleLsrIterator *remainingIter, UErrorCode &errorCode) const;
+
+ const XLikelySubtags &likelySubtags;
+ const LocaleDistance &localeDistance;
+ int32_t thresholdDistance;
+ int32_t demotionPerDesiredLocale;
+ ULocMatchFavorSubtag favorSubtag;
+ ULocMatchDirection direction;
+
+ // These are in input order.
+ const Locale ** supportedLocales;
+ LSR *lsrs;
+ int32_t supportedLocalesLength;
+ // These are in preference order: 1. Default locale 2. paradigm locales 3. others.
+ UHashtable *supportedLsrToIndex; // Map<LSR, Integer> stores index+1 because 0 is "not found"
+ // Array versions of the supportedLsrToIndex keys and values.
+ // The distance lookup loops over the supportedLSRs and returns the index of the best match.
+ const LSR **supportedLSRs;
+ int32_t *supportedIndexes;
+ int32_t supportedLSRsLength;
+ Locale *ownedDefaultLocale;
+ const Locale *defaultLocale;
+};
+
+U_NAMESPACE_END
+
+#endif // U_FORCE_HIDE_DRAFT_API
+#endif // U_SHOW_CPLUSPLUS_API
+#endif // __LOCALEMATCHER_H__