icuSources/i18n/unicode/upluralrules.h

   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 #ifndef U_HIDE_DRAFT_API
  41 /**
  42  * Type of plurals and PluralRules.
  43  * @draft ICU 50
  44  */
  45 enum UPluralType {
  46     /**
  47      * Plural rules for cardinal numbers: 1 file vs. 2 files.
  48      * @draft ICU 50
  49      */
  50     UPLURAL_TYPE_CARDINAL,
  51     /**
  52      * Plural rules for ordinal numbers: 1st file, 2nd file, 3rd file, 4th file, etc.
  53      * @draft ICU 50
  54      */
  55     UPLURAL_TYPE_ORDINAL,
  56     /**
  57      * Number of Plural rules types.
  58      * @draft ICU 50
  59      */
  60     UPLURAL_TYPE_COUNT
  61 };
  62 /**
  63  * @draft ICU 50
  64  */
  65 typedef enum UPluralType UPluralType;
  66 #endif /* U_HIDE_DRAFT_API */
  67
  68 /**
  69  * Opaque UPluralRules object for use in C programs.
  70  * @stable ICU 4.8
  71  */
  72 struct UPluralRules;
  73 typedef struct UPluralRules UPluralRules;  /**< C typedef for struct UPluralRules. @stable ICU 4.8 */
  74
  75 /**
  76  * Opens a new UPluralRules object using the predefined cardinal-number plural rules for a
  77  * given locale.
  78  * Same as uplrules_openForType(locale, UPLURAL_TYPE_CARDINAL, status).
  79  * @param locale The locale for which the rules are desired.
  80  * @param status A pointer to a UErrorCode to receive any errors.
  81  * @return A UPluralRules for the specified locale, or NULL if an error occurred.
  82  * @stable ICU 4.8
  83  */
  84 U_STABLE UPluralRules* U_EXPORT2
  85 uplrules_open(const char *locale, UErrorCode *status);
  86
  87 #ifndef U_HIDE_DRAFT_API
  88 /**
  89  * Opens a new UPluralRules object using the predefined plural rules for a
  90  * given locale and the plural type.
  91  * @param locale The locale for which the rules are desired.
  92  * @param type The plural type (e.g., cardinal or ordinal).
  93  * @param status A pointer to a UErrorCode to receive any errors.
  94  * @return A UPluralRules for the specified locale, or NULL if an error occurred.
  95  * @draft ICU 50
  96  */
  97 U_DRAFT UPluralRules* U_EXPORT2
  98 uplrules_openForType(const char *locale, UPluralType type, UErrorCode *status);
  99 #endif /* U_HIDE_DRAFT_API */
 100
 101 /**
 102  * Closes a UPluralRules object. Once closed it may no longer be used.
 103  * @param uplrules The UPluralRules object to close.
 104  * @stable ICU 4.8
 105  */
 106 U_STABLE void U_EXPORT2
 107 uplrules_close(UPluralRules *uplrules);
 108
 109
 110 #if U_SHOW_CPLUSPLUS_API
 111
 112 U_NAMESPACE_BEGIN
 113
 114 /**
 115  * \class LocalUPluralRulesPointer
 116  * "Smart pointer" class, closes a UPluralRules via uplrules_close().
 117  * For most methods see the LocalPointerBase base class.
 118  *
 119  * @see LocalPointerBase
 120  * @see LocalPointer
 121  * @stable ICU 4.8
 122  */
 123 U_DEFINE_LOCAL_OPEN_POINTER(LocalUPluralRulesPointer, UPluralRules, uplrules_close);
 124
 125 U_NAMESPACE_END
 126
 127 #endif
 128
 129
 130 /**
 131  * Given a number, returns the keyword of the first rule that
 132  * applies to the number, according to the supplied UPluralRules object.
 133  * @param uplrules The UPluralRules object specifying the rules.
 134  * @param number The number for which the rule has to be determined.
 135  * @param keyword The keyword of the rule that applies to number.
 136  * @param capacity The capacity of keyword.
 137  * @param status A pointer to a UErrorCode to receive any errors.
 138  * @return The length of keyword.
 139  * @stable ICU 4.8
 140  */
 141 U_STABLE int32_t U_EXPORT2
 142 uplrules_select(const UPluralRules *uplrules,
 143                double number,
 144                UChar *keyword, int32_t capacity,
 145                UErrorCode *status);
 146
 147 #endif /* #if !UCONFIG_NO_FORMATTING */
 148
 149 #endif