| // © 2016 and later: Unicode, Inc. and others. |
| // License & terms of use: http://www.unicode.org/copyright.html |
| /* |
| ******************************************************************************* |
| * Copyright (C) 2007-2014, International Business Machines Corporation and |
| * others. All Rights Reserved. |
| ******************************************************************************* |
| * |
| |
| * File PLURFMT.H |
| ******************************************************************************** |
| */ |
| |
| #ifndef PLURFMT |
| #define PLURFMT |
| |
| #include "unicode/utypes.h" |
| |
| #if U_SHOW_CPLUSPLUS_API |
| |
| /** |
| * \file |
| * \brief C++ API: PluralFormat object |
| */ |
| |
| #if !UCONFIG_NO_FORMATTING |
| |
| #include "unicode/messagepattern.h" |
| #include "unicode/numfmt.h" |
| #include "unicode/plurrule.h" |
| |
| U_NAMESPACE_BEGIN |
| |
| class Hashtable; |
| class NFRule; |
| |
| /** |
| * <p> |
| * <code>PluralFormat</code> supports the creation of internationalized |
| * messages with plural inflection. It is based on <i>plural |
| * selection</i>, i.e. the caller specifies messages for each |
| * plural case that can appear in the user's language and the |
| * <code>PluralFormat</code> selects the appropriate message based on |
| * the number. |
| * </p> |
| * <h4>The Problem of Plural Forms in Internationalized Messages</h4> |
| * <p> |
| * Different languages have different ways to inflect |
| * plurals. Creating internationalized messages that include plural |
| * forms is only feasible when the framework is able to handle plural |
| * forms of <i>all</i> languages correctly. <code>ChoiceFormat</code> |
| * doesn't handle this well, because it attaches a number interval to |
| * each message and selects the message whose interval contains a |
| * given number. This can only handle a finite number of |
| * intervals. But in some languages, like Polish, one plural case |
| * applies to infinitely many intervals (e.g., the plural case applies to |
| * numbers ending with 2, 3, or 4 except those ending with 12, 13, or |
| * 14). Thus <code>ChoiceFormat</code> is not adequate. |
| * </p><p> |
| * <code>PluralFormat</code> deals with this by breaking the problem |
| * into two parts: |
| * <ul> |
| * <li>It uses <code>PluralRules</code> that can define more complex |
| * conditions for a plural case than just a single interval. These plural |
| * rules define both what plural cases exist in a language, and to |
| * which numbers these cases apply. |
| * <li>It provides predefined plural rules for many languages. Thus, the programmer |
| * need not worry about the plural cases of a language and |
| * does not have to define the plural cases; they can simply |
| * use the predefined keywords. The whole plural formatting of messages can |
| * be done using localized patterns from resource bundles. For predefined plural |
| * rules, see the CLDR <i>Language Plural Rules</i> page at |
| * http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html |
| * </ul> |
| * </p> |
| * <h4>Usage of <code>PluralFormat</code></h4> |
| * <p>Note: Typically, plural formatting is done via <code>MessageFormat</code> |
| * with a <code>plural</code> argument type, |
| * rather than using a stand-alone <code>PluralFormat</code>. |
| * </p><p> |
| * This discussion assumes that you use <code>PluralFormat</code> with |
| * a predefined set of plural rules. You can create one using one of |
| * the constructors that takes a <code>locale</code> object. To |
| * specify the message pattern, you can either pass it to the |
| * constructor or set it explicitly using the |
| * <code>applyPattern()</code> method. The <code>format()</code> |
| * method takes a number object and selects the message of the |
| * matching plural case. This message will be returned. |
| * </p> |
| * <h5>Patterns and Their Interpretation</h5> |
| * <p> |
| * The pattern text defines the message output for each plural case of the |
| * specified locale. Syntax: |
| * <pre> |
| * pluralStyle = [offsetValue] (selector '{' message '}')+ |
| * offsetValue = "offset:" number |
| * selector = explicitValue | keyword |
| * explicitValue = '=' number // adjacent, no white space in between |
| * keyword = [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+ |
| * message: see {@link MessageFormat} |
| * </pre> |
| * Pattern_White_Space between syntax elements is ignored, except |
| * between the {curly braces} and their sub-message, |
| * and between the '=' and the number of an explicitValue. |
| * |
| * </p><p> |
| * There are 6 predefined casekeyword in CLDR/ICU - 'zero', 'one', 'two', 'few', 'many' and |
| * 'other'. You always have to define a message text for the default plural case |
| * <code>other</code> which is contained in every rule set. |
| * If you do not specify a message text for a particular plural case, the |
| * message text of the plural case <code>other</code> gets assigned to this |
| * plural case. |
| * </p><p> |
| * When formatting, the input number is first matched against the explicitValue clauses. |
| * If there is no exact-number match, then a keyword is selected by calling |
| * the <code>PluralRules</code> with the input number <em>minus the offset</em>. |
| * (The offset defaults to 0 if it is omitted from the pattern string.) |
| * If there is no clause with that keyword, then the "other" clauses is returned. |
| * </p><p> |
| * An unquoted pound sign (<code>#</code>) in the selected sub-message |
| * itself (i.e., outside of arguments nested in the sub-message) |
| * is replaced by the input number minus the offset. |
| * The number-minus-offset value is formatted using a |
| * <code>NumberFormat</code> for the <code>PluralFormat</code>'s locale. If you |
| * need special number formatting, you have to use a <code>MessageFormat</code> |
| * and explicitly specify a <code>NumberFormat</code> argument. |
| * <strong>Note:</strong> That argument is formatting without subtracting the offset! |
| * If you need a custom format and have a non-zero offset, then you need to pass the |
| * number-minus-offset value as a separate parameter. |
| * </p> |
| * For a usage example, see the {@link MessageFormat} class documentation. |
| * |
| * <h4>Defining Custom Plural Rules</h4> |
| * <p>If you need to use <code>PluralFormat</code> with custom rules, you can |
| * create a <code>PluralRules</code> object and pass it to |
| * <code>PluralFormat</code>'s constructor. If you also specify a locale in this |
| * constructor, this locale will be used to format the number in the message |
| * texts. |
| * </p><p> |
| * For more information about <code>PluralRules</code>, see |
| * {@link PluralRules}. |
| * </p> |
| * |
| * ported from Java |
| * @stable ICU 4.0 |
| */ |
| |
| class U_I18N_API PluralFormat : public Format { |
| public: |
| |
| /** |
| * Creates a new cardinal-number <code>PluralFormat</code> for the default locale. |
| * This locale will be used to get the set of plural rules and for standard |
| * number formatting. |
| * @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 |
| */ |
| PluralFormat(UErrorCode& status); |
| |
| /** |
| * Creates a new cardinal-number <code>PluralFormat</code> for a given locale. |
| * @param locale the <code>PluralFormat</code> will be configured with |
| * rules for this locale. This locale will also be used for |
| * standard number formatting. |
| * @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 |
| */ |
| PluralFormat(const Locale& locale, UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for a given set of rules. |
| * The standard number formatting will be done using the default locale. |
| * @param rules defines the behavior of the <code>PluralFormat</code> |
| * object. |
| * @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 |
| */ |
| PluralFormat(const PluralRules& rules, UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for a given set of rules. |
| * The standard number formatting will be done using the given locale. |
| * @param locale the default number formatting will be done using this |
| * locale. |
| * @param rules defines the behavior of the <code>PluralFormat</code> |
| * object. |
| * @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 |
| * <p> |
| * <h4>Sample code</h4> |
| * \snippet samples/plurfmtsample/plurfmtsample.cpp PluralFormatExample1 |
| * \snippet samples/plurfmtsample/plurfmtsample.cpp PluralFormatExample |
| * <p> |
| */ |
| PluralFormat(const Locale& locale, const PluralRules& rules, UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for the plural type. |
| * The standard number formatting will be done using the given locale. |
| * @param locale the default number formatting will be done using this |
| * locale. |
| * @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. |
| * @stable ICU 50 |
| */ |
| PluralFormat(const Locale& locale, UPluralType type, UErrorCode& status); |
| |
| /** |
| * Creates a new cardinal-number <code>PluralFormat</code> for a given pattern string. |
| * The default locale will be used to get the set of plural rules and for |
| * standard number formatting. |
| * @param pattern the pattern for this <code>PluralFormat</code>. |
| * errors are returned to status if the pattern is invalid. |
| * @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 |
| */ |
| PluralFormat(const UnicodeString& pattern, UErrorCode& status); |
| |
| /** |
| * Creates a new cardinal-number <code>PluralFormat</code> for a given pattern string and |
| * locale. |
| * The locale will be used to get the set of plural rules and for |
| * standard number formatting. |
| * @param locale the <code>PluralFormat</code> will be configured with |
| * rules for this locale. This locale will also be used for |
| * standard number formatting. |
| * @param pattern the pattern for this <code>PluralFormat</code>. |
| * errors are returned to status if the pattern is invalid. |
| * @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 |
| */ |
| PluralFormat(const Locale& locale, const UnicodeString& pattern, UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for a given set of rules, a |
| * pattern and a locale. |
| * @param rules defines the behavior of the <code>PluralFormat</code> |
| * object. |
| * @param pattern the pattern for this <code>PluralFormat</code>. |
| * errors are returned to status if the pattern is invalid. |
| * @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 |
| */ |
| PluralFormat(const PluralRules& rules, |
| const UnicodeString& pattern, |
| UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for a given set of rules, a |
| * pattern and a locale. |
| * @param locale the <code>PluralFormat</code> will be configured with |
| * rules for this locale. This locale will also be used for |
| * standard number formatting. |
| * @param rules defines the behavior of the <code>PluralFormat</code> |
| * object. |
| * @param pattern the pattern for this <code>PluralFormat</code>. |
| * errors are returned to status if the pattern is invalid. |
| * @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 |
| */ |
| PluralFormat(const Locale& locale, |
| const PluralRules& rules, |
| const UnicodeString& pattern, |
| UErrorCode& status); |
| |
| /** |
| * Creates a new <code>PluralFormat</code> for a plural type, a |
| * pattern and a locale. |
| * @param locale the <code>PluralFormat</code> will be configured with |
| * rules for this locale. This locale will also be used for |
| * standard number formatting. |
| * @param type The plural type (e.g., cardinal or ordinal). |
| * @param pattern the pattern for this <code>PluralFormat</code>. |
| * errors are returned to status if the pattern is invalid. |
| * @param status output param set to success/failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @stable ICU 50 |
| */ |
| PluralFormat(const Locale& locale, |
| UPluralType type, |
| const UnicodeString& pattern, |
| UErrorCode& status); |
| |
| /** |
| * copy constructor. |
| * @stable ICU 4.0 |
| */ |
| PluralFormat(const PluralFormat& other); |
| |
| /** |
| * Destructor. |
| * @stable ICU 4.0 |
| */ |
| virtual ~PluralFormat(); |
| |
| /** |
| * Sets the pattern used by this plural format. |
| * The method parses the pattern and creates a map of format strings |
| * for the plural rules. |
| * Patterns and their interpretation are specified in the class description. |
| * |
| * @param pattern the pattern for this plural format |
| * errors are returned to status if the pattern is invalid. |
| * @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 |
| */ |
| void applyPattern(const UnicodeString& pattern, UErrorCode& status); |
| |
| |
| using Format::format; |
| |
| /** |
| * Formats a plural message for a given number. |
| * |
| * @param number a number for which the plural message should be formatted |
| * for. If no pattern has been applied to this |
| * <code>PluralFormat</code> object yet, the formatted number |
| * will be returned. |
| * @param status output param set to success/failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @return the string containing the formatted plural message. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString format(int32_t number, UErrorCode& status) const; |
| |
| /** |
| * Formats a plural message for a given number. |
| * |
| * @param number a number for which the plural message should be formatted |
| * for. If no pattern has been applied to this |
| * PluralFormat object yet, the formatted number |
| * will be returned. |
| * @param status output param set to success or failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @return the string containing the formatted plural message. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString format(double number, UErrorCode& status) const; |
| |
| /** |
| * Formats a plural message for a given number. |
| * |
| * @param number a number for which the plural message should be formatted |
| * for. If no pattern has been applied to this |
| * <code>PluralFormat</code> object yet, the formatted number |
| * will be returned. |
| * @param appendTo output parameter to receive result. |
| * result is appended to existing contents. |
| * @param pos On input: an alignment field, if desired. |
| * On output: the offsets of the alignment field. |
| * @param status output param set to success/failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @return the string containing the formatted plural message. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString& format(int32_t number, |
| UnicodeString& appendTo, |
| FieldPosition& pos, |
| UErrorCode& status) const; |
| |
| /** |
| * Formats a plural message for a given number. |
| * |
| * @param number a number for which the plural message should be formatted |
| * for. If no pattern has been applied to this |
| * PluralFormat object yet, the formatted number |
| * will be returned. |
| * @param appendTo output parameter to receive result. |
| * result is appended to existing contents. |
| * @param pos On input: an alignment field, if desired. |
| * On output: the offsets of the alignment field. |
| * @param status output param set to success/failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @return the string containing the formatted plural message. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString& format(double number, |
| UnicodeString& appendTo, |
| FieldPosition& pos, |
| UErrorCode& status) const; |
| |
| #ifndef U_HIDE_DEPRECATED_API |
| /** |
| * Sets the locale used by this <code>PluraFormat</code> object. |
| * Note: Calling this method resets this <code>PluraFormat</code> object, |
| * i.e., a pattern that was applied previously will be removed, |
| * and the NumberFormat is set to the default number format for |
| * the locale. The resulting format behaves the same as one |
| * constructed from {@link #PluralFormat(const Locale& locale, UPluralType type, UErrorCode& status)} |
| * with UPLURAL_TYPE_CARDINAL. |
| * @param locale the <code>locale</code> to use to configure the formatter. |
| * @param status output param set to success/failure code on exit, which |
| * must not indicate a failure before the function call. |
| * @deprecated ICU 50 This method clears the pattern and might create |
| * a different kind of PluralRules instance; |
| * use one of the constructors to create a new instance instead. |
| */ |
| void setLocale(const Locale& locale, UErrorCode& status); |
| #endif /* U_HIDE_DEPRECATED_API */ |
| |
| /** |
| * Sets the number format used by this formatter. You only need to |
| * call this if you want a different number format than the default |
| * formatter for the locale. |
| * @param format the number format to use. |
| * @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 |
| */ |
| void setNumberFormat(const NumberFormat* format, UErrorCode& status); |
| |
| /** |
| * Assignment operator |
| * |
| * @param other the PluralFormat object to copy from. |
| * @stable ICU 4.0 |
| */ |
| PluralFormat& operator=(const PluralFormat& other); |
| |
| /** |
| * Return true if another object is semantically equal to this one. |
| * |
| * @param other the PluralFormat object to be compared with. |
| * @return true if other is semantically equal to this. |
| * @stable ICU 4.0 |
| */ |
| virtual UBool operator==(const Format& other) const; |
| |
| /** |
| * Return true if another object is semantically unequal to this one. |
| * |
| * @param other the PluralFormat object to be compared with. |
| * @return true if other is semantically unequal to this. |
| * @stable ICU 4.0 |
| */ |
| virtual UBool operator!=(const Format& other) const; |
| |
| /** |
| * Clones this Format object polymorphically. The caller owns the |
| * result and should delete it when done. |
| * @stable ICU 4.0 |
| */ |
| virtual PluralFormat* clone() const; |
| |
| /** |
| * Formats a plural message for a number taken from a Formattable object. |
| * |
| * @param obj The object containing a number for which the |
| * plural message should be formatted. |
| * The object must be of a numeric type. |
| * @param appendTo output parameter to receive result. |
| * Result is appended to existing contents. |
| * @param pos On input: an alignment field, if desired. |
| * On output: the offsets of the alignment field. |
| * @param status output param filled with success/failure status. |
| * @return Reference to 'appendTo' parameter. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString& format(const Formattable& obj, |
| UnicodeString& appendTo, |
| FieldPosition& pos, |
| UErrorCode& status) const; |
| |
| /** |
| * Returns the pattern from applyPattern() or constructor(). |
| * |
| * @param appendTo output parameter to receive result. |
| * Result is appended to existing contents. |
| * @return the UnicodeString with inserted pattern. |
| * @stable ICU 4.0 |
| */ |
| UnicodeString& toPattern(UnicodeString& appendTo); |
| |
| /** |
| * This method is not yet supported by <code>PluralFormat</code>. |
| * <P> |
| * Before calling, set parse_pos.index to the offset you want to start |
| * parsing at in the source. After calling, parse_pos.index is the end of |
| * the text you parsed. If error occurs, index is unchanged. |
| * <P> |
| * When parsing, leading whitespace is discarded (with a successful parse), |
| * while trailing whitespace is left as is. |
| * <P> |
| * See Format::parseObject() for more. |
| * |
| * @param source The string to be parsed into an object. |
| * @param result Formattable to be set to the parse result. |
| * If parse fails, return contents are undefined. |
| * @param parse_pos The position to start parsing at. Upon return |
| * this param is set to the position after the |
| * last character successfully parsed. If the |
| * source is not parsed successfully, this param |
| * will remain unchanged. |
| * @stable ICU 4.0 |
| */ |
| virtual void parseObject(const UnicodeString& source, |
| Formattable& result, |
| ParsePosition& parse_pos) const; |
| |
| /** |
| * 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; |
| |
| private: |
| /** |
| * @internal |
| */ |
| class U_I18N_API PluralSelector : public UMemory { |
| public: |
| virtual ~PluralSelector(); |
| /** |
| * Given a number, returns the appropriate PluralFormat keyword. |
| * |
| * @param context worker object for the selector. |
| * @param number The number to be plural-formatted. |
| * @param ec Error code. |
| * @return The selected PluralFormat keyword. |
| * @internal |
| */ |
| virtual UnicodeString select(void *context, double number, UErrorCode& ec) const = 0; |
| }; |
| |
| /** |
| * @internal |
| */ |
| class U_I18N_API PluralSelectorAdapter : public PluralSelector { |
| public: |
| PluralSelectorAdapter() : pluralRules(NULL) { |
| } |
| |
| virtual ~PluralSelectorAdapter(); |
| |
| virtual UnicodeString select(void *context, double number, UErrorCode& /*ec*/) const; /**< @internal */ |
| |
| void reset(); |
| |
| PluralRules* pluralRules; |
| }; |
| |
| Locale locale; |
| MessagePattern msgPattern; |
| NumberFormat* numberFormat; |
| double offset; |
| PluralSelectorAdapter pluralRulesWrapper; |
| |
| PluralFormat(); // default constructor not implemented |
| void init(const PluralRules* rules, UPluralType type, UErrorCode& status); |
| /** |
| * Copies dynamically allocated values (pointer fields). |
| * Others are copied using their copy constructors and assignment operators. |
| */ |
| void copyObjects(const PluralFormat& other); |
| |
| UnicodeString& format(const Formattable& numberObject, double number, |
| UnicodeString& appendTo, |
| FieldPosition& pos, |
| UErrorCode& status) const; /**< @internal */ |
| |
| /** |
| * Finds the PluralFormat sub-message for the given number, or the "other" sub-message. |
| * @param pattern A MessagePattern. |
| * @param partIndex the index of the first PluralFormat argument style part. |
| * @param selector the PluralSelector for mapping the number (minus offset) to a keyword. |
| * @param context worker object for the selector. |
| * @param number a number to be matched to one of the PluralFormat argument's explicit values, |
| * or mapped via the PluralSelector. |
| * @param ec ICU error code. |
| * @return the sub-message start part index. |
| */ |
| static int32_t findSubMessage( |
| const MessagePattern& pattern, int32_t partIndex, |
| const PluralSelector& selector, void *context, double number, UErrorCode& ec); /**< @internal */ |
| |
| void parseType(const UnicodeString& source, const NFRule *rbnfLenientScanner, |
| Formattable& result, FieldPosition& pos) const; |
| |
| friend class MessageFormat; |
| friend class NFRule; |
| }; |
| |
| U_NAMESPACE_END |
| |
| #endif /* #if !UCONFIG_NO_FORMATTING */ |
| |
| #endif /* U_SHOW_CPLUSPLUS_API */ |
| |
| #endif // _PLURFMT |
| //eof |
