upluralrules.h (8997B)
1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ***************************************************************************************** 5 * Copyright (C) 2010-2013, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ***************************************************************************************** 8 */ 9 10 #ifndef UPLURALRULES_H 11 #define UPLURALRULES_H 12 13 #include "unicode/utypes.h" 14 15 #if !UCONFIG_NO_FORMATTING 16 17 #include "unicode/uenum.h" 18 19 #if U_SHOW_CPLUSPLUS_API 20 #include "unicode/localpointer.h" 21 #endif // U_SHOW_CPLUSPLUS_API 22 23 #ifndef U_HIDE_INTERNAL_API 24 #include "unicode/unum.h" 25 #endif /* U_HIDE_INTERNAL_API */ 26 27 // Forward-declaration 28 struct UFormattedNumber; 29 struct UFormattedNumberRange; 30 31 /** 32 * \file 33 * \brief C API: Plural rules, select plural keywords for numeric values. 34 * 35 * A UPluralRules object defines rules for mapping non-negative numeric 36 * values onto a small set of keywords. Rules are constructed from a text 37 * description, consisting of a series of keywords and conditions. 38 * The uplrules_select function examines each condition in order and 39 * returns the keyword for the first condition that matches the number. 40 * If none match, the default rule(other) is returned. 41 * 42 * For more information, see the 43 * LDML spec, Part 3.5 Language Plural Rules: 44 * https://www.unicode.org/reports/tr35/tr35-numbers.html#Language_Plural_Rules 45 * 46 * Keywords: ICU locale data has 6 predefined values - 47 * 'zero', 'one', 'two', 'few', 'many' and 'other'. Callers need to check 48 * the value of keyword returned by the uplrules_select function. 49 * 50 * These are based on CLDR <i>Language Plural Rules</i>. For these 51 * predefined rules, see the CLDR page at 52 * https://unicode-org.github.io/cldr-staging/charts/latest/supplemental/language_plural_rules.html 53 */ 54 55 /** 56 * Type of plurals and PluralRules. 57 * @stable ICU 50 58 */ 59 enum UPluralType { 60 /** 61 * Plural rules for cardinal numbers: 1 file vs. 2 files. 62 * @stable ICU 50 63 */ 64 UPLURAL_TYPE_CARDINAL, 65 /** 66 * Plural rules for ordinal numbers: 1st file, 2nd file, 3rd file, 4th file, etc. 67 * @stable ICU 50 68 */ 69 UPLURAL_TYPE_ORDINAL, 70 #ifndef U_HIDE_DEPRECATED_API 71 /** 72 * One more than the highest normal UPluralType value. 73 * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420. 74 */ 75 UPLURAL_TYPE_COUNT 76 #endif /* U_HIDE_DEPRECATED_API */ 77 }; 78 /** 79 * @stable ICU 50 80 */ 81 typedef enum UPluralType UPluralType; 82 83 /** 84 * Opaque UPluralRules object for use in C programs. 85 * @stable ICU 4.8 86 */ 87 struct UPluralRules; 88 typedef struct UPluralRules UPluralRules; /**< C typedef for struct UPluralRules. @stable ICU 4.8 */ 89 90 /** 91 * Opens a new UPluralRules object using the predefined cardinal-number plural rules for a 92 * given locale. 93 * Same as uplrules_openForType(locale, UPLURAL_TYPE_CARDINAL, status). 94 * @param locale The locale for which the rules are desired. 95 * @param status A pointer to a UErrorCode to receive any errors. 96 * @return A UPluralRules for the specified locale, or NULL if an error occurred. 97 * @stable ICU 4.8 98 */ 99 U_CAPI UPluralRules* U_EXPORT2 100 uplrules_open(const char *locale, UErrorCode *status); 101 102 /** 103 * Opens a new UPluralRules object using the predefined plural rules for a 104 * given locale and the plural type. 105 * @param locale The locale for which the rules are desired. 106 * @param type The plural type (e.g., cardinal or ordinal). 107 * @param status A pointer to a UErrorCode to receive any errors. 108 * @return A UPluralRules for the specified locale, or NULL if an error occurred. 109 * @stable ICU 50 110 */ 111 U_CAPI UPluralRules* U_EXPORT2 112 uplrules_openForType(const char *locale, UPluralType type, UErrorCode *status); 113 114 /** 115 * Closes a UPluralRules object. Once closed it may no longer be used. 116 * @param uplrules The UPluralRules object to close. 117 * @stable ICU 4.8 118 */ 119 U_CAPI void U_EXPORT2 120 uplrules_close(UPluralRules *uplrules); 121 122 123 #if U_SHOW_CPLUSPLUS_API 124 125 U_NAMESPACE_BEGIN 126 127 /** 128 * \class LocalUPluralRulesPointer 129 * "Smart pointer" class, closes a UPluralRules via uplrules_close(). 130 * For most methods see the LocalPointerBase base class. 131 * 132 * @see LocalPointerBase 133 * @see LocalPointer 134 * @stable ICU 4.8 135 */ 136 U_DEFINE_LOCAL_OPEN_POINTER(LocalUPluralRulesPointer, UPluralRules, uplrules_close); 137 138 U_NAMESPACE_END 139 140 #endif 141 142 143 /** 144 * Given a floating-point number, returns the keyword of the first rule that 145 * applies to the number, according to the supplied UPluralRules object. 146 * @param uplrules The UPluralRules object specifying the rules. 147 * @param number The number for which the rule has to be determined. 148 * @param keyword An output buffer to write the keyword of the rule that 149 * applies to number. 150 * @param capacity The capacity of the keyword buffer. 151 * @param status A pointer to a UErrorCode to receive any errors. 152 * @return The length of the keyword. 153 * @stable ICU 4.8 154 */ 155 U_CAPI int32_t U_EXPORT2 156 uplrules_select(const UPluralRules *uplrules, 157 double number, 158 UChar *keyword, int32_t capacity, 159 UErrorCode *status); 160 161 /** 162 * Given a formatted number, returns the keyword of the first rule 163 * that applies to the number, according to the supplied UPluralRules object. 164 * 165 * A UFormattedNumber allows you to specify an exponent or trailing zeros, 166 * which can affect the plural category. To get a UFormattedNumber, see 167 * {@link UNumberFormatter}. 168 * 169 * @param uplrules The UPluralRules object specifying the rules. 170 * @param number The formatted number for which the rule has to be determined. 171 * @param keyword The destination buffer for the keyword of the rule that 172 * applies to the number. 173 * @param capacity The capacity of the keyword buffer. 174 * @param status A pointer to a UErrorCode to receive any errors. 175 * @return The length of the keyword. 176 * @stable ICU 64 177 */ 178 U_CAPI int32_t U_EXPORT2 179 uplrules_selectFormatted(const UPluralRules *uplrules, 180 const struct UFormattedNumber* number, 181 UChar *keyword, int32_t capacity, 182 UErrorCode *status); 183 184 /** 185 * Given a formatted number range, returns the overall plural form of the 186 * range. For example, "3-5" returns "other" in English. 187 * 188 * To get a UFormattedNumberRange, see UNumberRangeFormatter. 189 * 190 * @param uplrules The UPluralRules object specifying the rules. 191 * @param urange The number range onto which the rules will be applied. 192 * @param keyword The destination buffer for the keyword of the rule that 193 * applies to the number range. 194 * @param capacity The capacity of the keyword buffer. 195 * @param status A pointer to a UErrorCode to receive any errors. 196 * @return The length of the keyword. 197 * @stable ICU 68 198 */ 199 U_CAPI int32_t U_EXPORT2 200 uplrules_selectForRange(const UPluralRules *uplrules, 201 const struct UFormattedNumberRange* urange, 202 UChar *keyword, int32_t capacity, 203 UErrorCode *status); 204 205 #ifndef U_HIDE_INTERNAL_API 206 /** 207 * Given a number, returns the keyword of the first rule that applies to the 208 * number, according to the UPluralRules object and given the number format 209 * specified by the UNumberFormat object. 210 * Note: This internal preview interface may be removed in the future if 211 * an architecturally cleaner solution reaches stable status. 212 * @param uplrules The UPluralRules object specifying the rules. 213 * @param number The number for which the rule has to be determined. 214 * @param fmt The UNumberFormat specifying how the number will be formatted 215 * (this can affect the plural form, e.g. "1 dollar" vs "1.0 dollars"). 216 * If this is NULL, the function behaves like uplrules_select. 217 * @param keyword An output buffer to write the keyword of the rule that 218 * applies to number. 219 * @param capacity The capacity of the keyword buffer. 220 * @param status A pointer to a UErrorCode to receive any errors. 221 * @return The length of keyword. 222 * @internal ICU 59 technology preview, may be removed in the future 223 */ 224 U_CAPI int32_t U_EXPORT2 225 uplrules_selectWithFormat(const UPluralRules *uplrules, 226 double number, 227 const UNumberFormat *fmt, 228 UChar *keyword, int32_t capacity, 229 UErrorCode *status); 230 231 #endif /* U_HIDE_INTERNAL_API */ 232 233 /** 234 * Creates a string enumeration of all plural rule keywords used in this 235 * UPluralRules object. The rule "other" is always present by default. 236 * @param uplrules The UPluralRules object specifying the rules for 237 * a given locale. 238 * @param status A pointer to a UErrorCode to receive any errors. 239 * @return a string enumeration over plural rule keywords, or NULL 240 * upon error. The caller is responsible for closing the result. 241 * @stable ICU 59 242 */ 243 U_CAPI UEnumeration* U_EXPORT2 244 uplrules_getKeywords(const UPluralRules *uplrules, 245 UErrorCode *status); 246 247 #endif /* #if !UCONFIG_NO_FORMATTING */ 248 249 #endif