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diff --git a/intl/icu/source/i18n/unicode/plurrule.h b/intl/icu/source/i18n/unicode/plurrule.h new file mode 100644 index 0000000000..b7d95175f5 --- /dev/null +++ b/intl/icu/source/i18n/unicode/plurrule.h @@ -0,0 +1,591 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +******************************************************************************* +* Copyright (C) 2008-2015, International Business Machines Corporation and +* others. All Rights Reserved. +******************************************************************************* +* +* +* File PLURRULE.H +* +* Modification History:* +* Date Name Description +* +******************************************************************************** +*/ + +#ifndef PLURRULE +#define PLURRULE + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API + +/** + * \file + * \brief C++ API: PluralRules object + */ + +#if !UCONFIG_NO_FORMATTING + +#include "unicode/format.h" +#include "unicode/upluralrules.h" +#ifndef U_HIDE_INTERNAL_API +#include "unicode/numfmt.h" +#endif /* U_HIDE_INTERNAL_API */ + +/** + * Value returned by PluralRules::getUniqueKeywordValue() when there is no + * unique value to return. + * @stable ICU 4.8 + */ +#define UPLRULES_NO_UNIQUE_VALUE ((double)-0.00123456777) + +U_NAMESPACE_BEGIN + +class Hashtable; +class IFixedDecimal; +class FixedDecimal; +class RuleChain; +class PluralRuleParser; +class PluralKeywordEnumeration; +class AndConstraint; +class SharedPluralRules; +class StandardPluralRanges; + +namespace number { +class FormattedNumber; +class FormattedNumberRange; +namespace impl { +class UFormattedNumberRangeData; +class DecimalQuantity; +class DecNum; +} +} + +#ifndef U_HIDE_INTERNAL_API +using icu::number::impl::DecimalQuantity; +#endif /* U_HIDE_INTERNAL_API */ + +/** + * Defines rules for mapping non-negative numeric values onto a small set of + * keywords. Rules are constructed from a text description, consisting + * of a series of keywords and conditions. The {@link #select} method + * examines each condition in order and returns the keyword for the + * first condition that matches the number. If none match, + * default rule(other) is returned. + * + * For more information, details, and tips for writing rules, see the + * LDML spec, Part 3.5 Language Plural Rules: + * https://www.unicode.org/reports/tr35/tr35-numbers.html#Language_Plural_Rules + * + * Examples:<pre> + * "one: n is 1; few: n in 2..4"</pre> + * This defines two rules, for 'one' and 'few'. The condition for + * 'one' is "n is 1" which means that the number must be equal to + * 1 for this condition to pass. The condition for 'few' is + * "n in 2..4" which means that the number must be between 2 and + * 4 inclusive for this condition to pass. All other numbers + * are assigned the keyword "other" by the default rule. + * </p><pre> + * "zero: n is 0; one: n is 1; zero: n mod 100 in 1..19"</pre> + * This illustrates that the same keyword can be defined multiple times. + * Each rule is examined in order, and the first keyword whose condition + * passes is the one returned. Also notes that a modulus is applied + * to n in the last rule. Thus its condition holds for 119, 219, 319... + * </p><pre> + * "one: n is 1; few: n mod 10 in 2..4 and n mod 100 not in 12..14"</pre> + * This illustrates conjunction and negation. The condition for 'few' + * has two parts, both of which must be met: "n mod 10 in 2..4" and + * "n mod 100 not in 12..14". The first part applies a modulus to n + * before the test as in the previous example. The second part applies + * a different modulus and also uses negation, thus it matches all + * numbers _not_ in 12, 13, 14, 112, 113, 114, 212, 213, 214... + * </p> + * <p> + * Syntax:<pre> + * \code + * rules = rule (';' rule)* + * rule = keyword ':' condition + * keyword = <identifier> + * condition = and_condition ('or' and_condition)* + * and_condition = relation ('and' relation)* + * relation = is_relation | in_relation | within_relation | 'n' <EOL> + * is_relation = expr 'is' ('not')? value + * in_relation = expr ('not')? 'in' range_list + * within_relation = expr ('not')? 'within' range + * expr = ('n' | 'i' | 'f' | 'v' | 'j') ('mod' value)? + * range_list = (range | value) (',' range_list)* + * value = digit+ ('.' digit+)? + * digit = 0|1|2|3|4|5|6|7|8|9 + * range = value'..'value + * \endcode + * </pre></p> + * <p> + * <p> + * The i, f, and v values are defined as follows: + * </p> + * <ul> + * <li>i to be the integer digits.</li> + * <li>f to be the visible fractional digits, as an integer.</li> + * <li>v to be the number of visible fraction digits.</li> + * <li>j is defined to only match integers. That is j is 3 fails if v != 0 (eg for 3.1 or 3.0).</li> + * </ul> + * <p> + * Examples are in the following table: + * </p> + * <table border='1' style="border-collapse:collapse"> + * <tr> + * <th>n</th> + * <th>i</th> + * <th>f</th> + * <th>v</th> + * </tr> + * <tr> + * <td>1.0</td> + * <td>1</td> + * <td align="right">0</td> + * <td>1</td> + * </tr> + * <tr> + * <td>1.00</td> + * <td>1</td> + * <td align="right">0</td> + * <td>2</td> + * </tr> + * <tr> + * <td>1.3</td> + * <td>1</td> + * <td align="right">3</td> + * <td>1</td> + * </tr> + * <tr> + * <td>1.03</td> + * <td>1</td> + * <td align="right">3</td> + * <td>2</td> + * </tr> + * <tr> + * <td>1.23</td> + * <td>1</td> + * <td align="right">23</td> + * <td>2</td> + * </tr> + * </table> + * <p> + * The difference between 'in' and 'within' is that 'in' only includes integers in the specified range, while 'within' + * includes all values. Using 'within' with a range_list consisting entirely of values is the same as using 'in' (it's + * not an error). + * </p> + + * An "identifier" is a sequence of characters that do not have the + * Unicode Pattern_Syntax or Pattern_White_Space properties. + * <p> + * The difference between 'in' and 'within' is that 'in' only includes + * integers in the specified range, while 'within' includes all values. + * Using 'within' with a range_list consisting entirely of values is the + * same as using 'in' (it's not an error). + *</p> + * <p> + * Keywords + * could be defined by users or from ICU locale data. There are 6 + * predefined values in ICU - 'zero', 'one', 'two', 'few', 'many' and + * 'other'. Callers need to check the value of keyword returned by + * {@link #select} method. + * </p> + * + * Examples:<pre> + * UnicodeString keyword = pl->select(number); + * if (keyword== UnicodeString("one") { + * ... + * } + * else if ( ... ) + * </pre> + * <strong>Note:</strong><br> + * <p> + * ICU defines plural rules for many locales based on CLDR <i>Language Plural Rules</i>. + * For these predefined rules, see CLDR page at + * https://unicode-org.github.io/cldr-staging/charts/latest/supplemental/language_plural_rules.html + * </p> + */ +class U_I18N_API PluralRules : public UObject { +public: + + /** + * Constructor. + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * + * @stable ICU 4.0 + */ + PluralRules(UErrorCode& status); + + /** + * Copy constructor. + * @stable ICU 4.0 + */ + PluralRules(const PluralRules& other); + + /** + * Destructor. + * @stable ICU 4.0 + */ + virtual ~PluralRules(); + + /** + * Clone + * @stable ICU 4.0 + */ + PluralRules* clone() const; + + /** + * Assignment operator. + * @stable ICU 4.0 + */ + PluralRules& operator=(const PluralRules&); + + /** + * Creates a PluralRules from a description if it is parsable, otherwise + * returns nullptr. + * + * @param description rule description + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * @return new PluralRules pointer. nullptr if there is an error. + * @stable ICU 4.0 + */ + static PluralRules* U_EXPORT2 createRules(const UnicodeString& description, + UErrorCode& status); + + /** + * The default rules that accept any number. + * + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * @return new PluralRules pointer. nullptr if there is an error. + * @stable ICU 4.0 + */ + static PluralRules* U_EXPORT2 createDefaultRules(UErrorCode& status); + + /** + * Provides access to the predefined cardinal-number <code>PluralRules</code> for a given + * locale. + * Same as forLocale(locale, UPLURAL_TYPE_CARDINAL, status). + * + * @param locale The locale for which a <code>PluralRules</code> object is + * returned. + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * @return The predefined <code>PluralRules</code> object pointer for + * this locale. If there's no predefined rules for this locale, + * the rules for the closest parent in the locale hierarchy + * that has one will be returned. The final fallback always + * returns the default 'other' rules. + * @stable ICU 4.0 + */ + static PluralRules* U_EXPORT2 forLocale(const Locale& locale, UErrorCode& status); + + /** + * Provides access to the predefined <code>PluralRules</code> for a given + * locale and the plural type. + * + * @param locale The locale for which a <code>PluralRules</code> object is + * returned. + * @param type The plural type (e.g., cardinal or ordinal). + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * @return The predefined <code>PluralRules</code> object pointer for + * this locale. If there's no predefined rules for this locale, + * the rules for the closest parent in the locale hierarchy + * that has one will be returned. The final fallback always + * returns the default 'other' rules. + * @stable ICU 50 + */ + static PluralRules* U_EXPORT2 forLocale(const Locale& locale, UPluralType type, UErrorCode& status); + +#ifndef U_HIDE_INTERNAL_API + /** + * Return a StringEnumeration over the locales for which there is plurals data. + * @return a StringEnumeration over the locales available. + * @internal + */ + static StringEnumeration* U_EXPORT2 getAvailableLocales(UErrorCode &status); + + /** + * For ICU use only. + * creates a SharedPluralRules object + * @internal + */ + static PluralRules* U_EXPORT2 internalForLocale(const Locale& locale, UPluralType type, UErrorCode& status); + + /** + * For ICU use only. + * Returns handle to the shared, cached PluralRules instance. + * Caller must call removeRef() on returned value once it is done with + * the shared instance. + * @internal + */ + static const SharedPluralRules* U_EXPORT2 createSharedInstance( + const Locale& locale, UPluralType type, UErrorCode& status); + + +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Given an integer, returns the keyword of the first rule + * that applies to the number. This function can be used with + * isKeyword* functions to determine the keyword for default plural rules. + * + * @param number The number for which the rule has to be determined. + * @return The keyword of the selected rule. + * @stable ICU 4.0 + */ + UnicodeString select(int32_t number) const; + + /** + * Given a floating-point number, returns the keyword of the first rule + * that applies to the number. This function can be used with + * isKeyword* functions to determine the keyword for default plural rules. + * + * @param number The number for which the rule has to be determined. + * @return The keyword of the selected rule. + * @stable ICU 4.0 + */ + UnicodeString select(double number) const; + + /** + * Given a formatted number, returns the keyword of the first rule + * that applies to the number. This function can be used with + * isKeyword* functions to determine the keyword for default plural rules. + * + * A FormattedNumber allows you to specify an exponent or trailing zeros, + * which can affect the plural category. To get a FormattedNumber, see + * NumberFormatter. + * + * @param number The number for which the rule has to be determined. + * @param status Set if an error occurs while selecting plural keyword. + * This could happen if the FormattedNumber is invalid. + * @return The keyword of the selected rule. + * @stable ICU 64 + */ + UnicodeString select(const number::FormattedNumber& number, UErrorCode& status) const; + + /** + * Given a formatted number range, returns the overall plural form of the + * range. For example, "3-5" returns "other" in English. + * + * To get a FormattedNumberRange, see NumberRangeFormatter. + * + * This method only works if PluralRules was created with a locale. If it was created + * from PluralRules::createRules(), this method sets status code U_UNSUPPORTED_ERROR. + * + * @param range The number range onto which the rules will be applied. + * @param status Set if an error occurs while selecting plural keyword. + * This could happen if the FormattedNumberRange is invalid, + * or if plural ranges data is unavailable. + * @return The keyword of the selected rule. + * @stable ICU 68 + */ + UnicodeString select(const number::FormattedNumberRange& range, UErrorCode& status) const; + +#ifndef U_HIDE_INTERNAL_API + /** + * @internal + */ + UnicodeString select(const IFixedDecimal &number) const; + /** + * @internal + */ + UnicodeString select(const number::impl::UFormattedNumberRangeData* urange, UErrorCode& status) const; +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Returns a list of all rule keywords used in this <code>PluralRules</code> + * object. The rule 'other' is always present by default. + * + * @param status Output param set to success/failure code on exit, which + * must not indicate a failure before the function call. + * @return StringEnumeration with the keywords. + * The caller must delete the object. + * @stable ICU 4.0 + */ + StringEnumeration* getKeywords(UErrorCode& status) const; + +#ifndef U_HIDE_DEPRECATED_API + /** + * Deprecated Function, does not return useful results. + * + * Originally intended to return a unique value for this keyword if it exists, + * else the constant UPLRULES_NO_UNIQUE_VALUE. + * + * @param keyword The keyword. + * @return Stub deprecated function returns UPLRULES_NO_UNIQUE_VALUE always. + * @deprecated ICU 55 + */ + double getUniqueKeywordValue(const UnicodeString& keyword); + + /** + * Deprecated Function, does not produce useful results. + * + * Originally intended to return all the values for which select() would return the keyword. + * If the keyword is unknown, returns no values, but this is not an error. If + * the number of values is unlimited, returns no values and -1 as the + * count. + * + * The number of returned values is typically small. + * + * @param keyword The keyword. + * @param dest Array into which to put the returned values. May + * be nullptr if destCapacity is 0. + * @param destCapacity The capacity of the array, must be at least 0. + * @param status The error code. Deprecated function, always sets U_UNSUPPORTED_ERROR. + * @return The count of values available, or -1. This count + * can be larger than destCapacity, but no more than + * destCapacity values will be written. + * @deprecated ICU 55 + */ + int32_t getAllKeywordValues(const UnicodeString &keyword, + double *dest, int32_t destCapacity, + UErrorCode& status); +#endif /* U_HIDE_DEPRECATED_API */ + + /** + * Returns sample values for which select() would return the keyword. If + * the keyword is unknown, returns no values, but this is not an error. + * + * The number of returned values is typically small. + * + * @param keyword The keyword. + * @param dest Array into which to put the returned values. May + * be nullptr if destCapacity is 0. + * @param destCapacity The capacity of the array, must be at least 0. + * @param status The error code. + * @return The count of values written. + * If more than destCapacity samples are available, then + * only destCapacity are written, and destCapacity is returned as the count, + * rather than setting a U_BUFFER_OVERFLOW_ERROR. + * (The actual number of keyword values could be unlimited.) + * @stable ICU 4.8 + */ + int32_t getSamples(const UnicodeString &keyword, + double *dest, int32_t destCapacity, + UErrorCode& status); + +#ifndef U_HIDE_INTERNAL_API + /** + * Internal-only function that returns DecimalQuantitys instead of doubles. + * + * Returns sample values for which select() would return the keyword. If + * the keyword is unknown, returns no values, but this is not an error. + * + * The number of returned values is typically small. + * + * @param keyword The keyword. + * @param dest Array into which to put the returned values. May + * be nullptr if destCapacity is 0. + * @param destCapacity The capacity of the array, must be at least 0. + * @param status The error code. + * @return The count of values written. + * If more than destCapacity samples are available, then + * only destCapacity are written, and destCapacity is returned as the count, + * rather than setting a U_BUFFER_OVERFLOW_ERROR. + * (The actual number of keyword values could be unlimited.) + * @internal + */ + int32_t getSamples(const UnicodeString &keyword, + DecimalQuantity *dest, int32_t destCapacity, + UErrorCode& status); +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Returns true if the given keyword is defined in this + * <code>PluralRules</code> object. + * + * @param keyword the input keyword. + * @return true if the input keyword is defined. + * Otherwise, return false. + * @stable ICU 4.0 + */ + UBool isKeyword(const UnicodeString& keyword) const; + + + /** + * Returns keyword for default plural form. + * + * @return keyword for default plural form. + * @stable ICU 4.0 + */ + UnicodeString getKeywordOther() const; + +#ifndef U_HIDE_INTERNAL_API + /** + * + * @internal + */ + UnicodeString getRules() const; +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Compares the equality of two PluralRules objects. + * + * @param other The other PluralRules object to be compared with. + * @return true if the given PluralRules is the same as this + * PluralRules; false otherwise. + * @stable ICU 4.0 + */ + virtual bool operator==(const PluralRules& other) const; + + /** + * Compares the inequality of two PluralRules objects. + * + * @param other The PluralRules object to be compared with. + * @return true if the given PluralRules is not the same as this + * PluralRules; false otherwise. + * @stable ICU 4.0 + */ + bool operator!=(const PluralRules& other) const {return !operator==(other);} + + + /** + * ICU "poor man's RTTI", returns a UClassID for this class. + * + * @stable ICU 4.0 + * + */ + static UClassID U_EXPORT2 getStaticClassID(void); + + /** + * ICU "poor man's RTTI", returns a UClassID for the actual class. + * + * @stable ICU 4.0 + */ + virtual UClassID getDynamicClassID() const override; + + +private: + RuleChain *mRules; + StandardPluralRanges *mStandardPluralRanges; + + PluralRules() = delete; // default constructor not implemented + UnicodeString getRuleFromResource(const Locale& locale, UPluralType type, UErrorCode& status); + RuleChain *rulesForKeyword(const UnicodeString &keyword) const; + PluralRules *clone(UErrorCode& status) const; + + /** + * An internal status variable used to indicate that the object is in an 'invalid' state. + * Used by copy constructor, the assignment operator and the clone method. + */ + UErrorCode mInternalStatus; + + friend class PluralRuleParser; +}; + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_FORMATTING */ + +#endif /* U_SHOW_CPLUSPLUS_API */ + +#endif // _PLURRULE +//eof |