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      1 /*
      2 *****************************************************************************************
      3 * Copyright (C) 2010-2013, International Business Machines
      4 * Corporation and others. All Rights Reserved.
      5 *****************************************************************************************
      6 */
      7 
      8 #ifndef UPLURALRULES_H
      9 #define UPLURALRULES_H
     10 
     11 #include "unicode/utypes.h"
     12 
     13 #if !UCONFIG_NO_FORMATTING
     14 
     15 #include "unicode/localpointer.h"
     16 
     17 /**
     18  * \file
     19  * \brief C API: Plural rules, select plural keywords for numeric values.
     20  *
     21  * A UPluralRules object defines rules for mapping non-negative numeric
     22  * values onto a small set of keywords. Rules are constructed from a text
     23  * description, consisting of a series of keywords and conditions.
     24  * The uplrules_select function examines each condition in order and
     25  * returns the keyword for the first condition that matches the number.
     26  * If none match, the default rule(other) is returned.
     27  *
     28  * For more information, see the LDML spec, C.11 Language Plural Rules:
     29  * http://www.unicode.org/reports/tr35/#Language_Plural_Rules
     30  *
     31  * Keywords: ICU locale data has 6 predefined values -
     32  * 'zero', 'one', 'two', 'few', 'many' and 'other'. Callers need to check
     33  * the value of keyword returned by the uplrules_select function.
     34  *
     35  * These are based on CLDR <i>Language Plural Rules</i>. For these
     36  * predefined rules, see the CLDR page at
     37  * http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html
     38  */
     39 
     40 /**
     41  * Type of plurals and PluralRules.
     42  * @stable ICU 50
     43  */
     44 enum UPluralType {
     45     /**
     46      * Plural rules for cardinal numbers: 1 file vs. 2 files.
     47      * @stable ICU 50
     48      */
     49     UPLURAL_TYPE_CARDINAL,
     50     /**
     51      * Plural rules for ordinal numbers: 1st file, 2nd file, 3rd file, 4th file, etc.
     52      * @stable ICU 50
     53      */
     54     UPLURAL_TYPE_ORDINAL,
     55     /**
     56      * Number of Plural rules types.
     57      * @stable ICU 50
     58      */
     59     UPLURAL_TYPE_COUNT
     60 };
     61 /**
     62  * @stable ICU 50
     63  */
     64 typedef enum UPluralType UPluralType;
     65 
     66 /**
     67  * Opaque UPluralRules object for use in C programs.
     68  * @stable ICU 4.8
     69  */
     70 struct UPluralRules;
     71 typedef struct UPluralRules UPluralRules;  /**< C typedef for struct UPluralRules. @stable ICU 4.8 */
     72 
     73 /**
     74  * Opens a new UPluralRules object using the predefined cardinal-number plural rules for a
     75  * given locale.
     76  * Same as uplrules_openForType(locale, UPLURAL_TYPE_CARDINAL, status).
     77  * @param locale The locale for which the rules are desired.
     78  * @param status A pointer to a UErrorCode to receive any errors.
     79  * @return A UPluralRules for the specified locale, or NULL if an error occurred.
     80  * @stable ICU 4.8
     81  */
     82 U_STABLE UPluralRules* U_EXPORT2
     83 uplrules_open(const char *locale, UErrorCode *status);
     84 
     85 /**
     86  * Opens a new UPluralRules object using the predefined plural rules for a
     87  * given locale and the plural type.
     88  * @param locale The locale for which the rules are desired.
     89  * @param type The plural type (e.g., cardinal or ordinal).
     90  * @param status A pointer to a UErrorCode to receive any errors.
     91  * @return A UPluralRules for the specified locale, or NULL if an error occurred.
     92  * @stable ICU 50
     93  */
     94 U_DRAFT UPluralRules* U_EXPORT2
     95 uplrules_openForType(const char *locale, UPluralType type, UErrorCode *status);
     96 
     97 /**
     98  * Closes a UPluralRules object. Once closed it may no longer be used.
     99  * @param uplrules The UPluralRules object to close.
    100  * @stable ICU 4.8
    101  */
    102 U_STABLE void U_EXPORT2
    103 uplrules_close(UPluralRules *uplrules);
    104 
    105 
    106 #if U_SHOW_CPLUSPLUS_API
    107 
    108 U_NAMESPACE_BEGIN
    109 
    110 /**
    111  * \class LocalUPluralRulesPointer
    112  * "Smart pointer" class, closes a UPluralRules via uplrules_close().
    113  * For most methods see the LocalPointerBase base class.
    114  *
    115  * @see LocalPointerBase
    116  * @see LocalPointer
    117  * @stable ICU 4.8
    118  */
    119 U_DEFINE_LOCAL_OPEN_POINTER(LocalUPluralRulesPointer, UPluralRules, uplrules_close);
    120 
    121 U_NAMESPACE_END
    122 
    123 #endif
    124 
    125 
    126 /**
    127  * Given a number, returns the keyword of the first rule that
    128  * applies to the number, according to the supplied UPluralRules object.
    129  * @param uplrules The UPluralRules object specifying the rules.
    130  * @param number The number for which the rule has to be determined.
    131  * @param keyword The keyword of the rule that applies to number.
    132  * @param capacity The capacity of keyword.
    133  * @param status A pointer to a UErrorCode to receive any errors.
    134  * @return The length of keyword.
    135  * @stable ICU 4.8
    136  */
    137 U_STABLE int32_t U_EXPORT2
    138 uplrules_select(const UPluralRules *uplrules,
    139                double number,
    140                UChar *keyword, int32_t capacity,
    141                UErrorCode *status);
    142 
    143 #endif /* #if !UCONFIG_NO_FORMATTING */
    144 
    145 #endif
    146