1 // 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ******************************************************************************* 5 * Copyright (C) 2008-2015, International Business Machines Corporation and 6 * others. All Rights Reserved. 7 ******************************************************************************* 8 * 9 * 10 * File PLURRULE.H 11 * 12 * Modification History:* 13 * Date Name Description 14 * 15 ******************************************************************************** 16 */ 17 18 #ifndef PLURRULE 19 #define PLURRULE 20 21 #include "unicode/utypes.h" 22 23 /** 24 * \file 25 * \brief C++ API: PluralRules object 26 */ 27 28 #if !UCONFIG_NO_FORMATTING 29 30 #include "unicode/format.h" 31 #include "unicode/upluralrules.h" 32 #ifndef U_HIDE_INTERNAL_API 33 #include "unicode/numfmt.h" 34 #endif /* U_HIDE_INTERNAL_API */ 35 36 /** 37 * Value returned by PluralRules::getUniqueKeywordValue() when there is no 38 * unique value to return. 39 * @stable ICU 4.8 40 */ 41 #define UPLRULES_NO_UNIQUE_VALUE ((double)-0.00123456777) 42 43 U_NAMESPACE_BEGIN 44 45 class Hashtable; 46 class IFixedDecimal; 47 class VisibleDigitsWithExponent; 48 class RuleChain; 49 class PluralRuleParser; 50 class PluralKeywordEnumeration; 51 class AndConstraint; 52 class SharedPluralRules; 53 54 /** 55 * Defines rules for mapping non-negative numeric values onto a small set of 56 * keywords. Rules are constructed from a text description, consisting 57 * of a series of keywords and conditions. The {@link #select} method 58 * examines each condition in order and returns the keyword for the 59 * first condition that matches the number. If none match, 60 * default rule(other) is returned. 61 * 62 * For more information, details, and tips for writing rules, see the 63 * LDML spec, C.11 Language Plural Rules: 64 * http://www.unicode.org/draft/reports/tr35/tr35.html#Language_Plural_Rules 65 * 66 * Examples:<pre> 67 * "one: n is 1; few: n in 2..4"</pre> 68 * This defines two rules, for 'one' and 'few'. The condition for 69 * 'one' is "n is 1" which means that the number must be equal to 70 * 1 for this condition to pass. The condition for 'few' is 71 * "n in 2..4" which means that the number must be between 2 and 72 * 4 inclusive for this condition to pass. All other numbers 73 * are assigned the keyword "other" by the default rule. 74 * </p><pre> 75 * "zero: n is 0; one: n is 1; zero: n mod 100 in 1..19"</pre> 76 * This illustrates that the same keyword can be defined multiple times. 77 * Each rule is examined in order, and the first keyword whose condition 78 * passes is the one returned. Also notes that a modulus is applied 79 * to n in the last rule. Thus its condition holds for 119, 219, 319... 80 * </p><pre> 81 * "one: n is 1; few: n mod 10 in 2..4 and n mod 100 not in 12..14"</pre> 82 * This illustrates conjunction and negation. The condition for 'few' 83 * has two parts, both of which must be met: "n mod 10 in 2..4" and 84 * "n mod 100 not in 12..14". The first part applies a modulus to n 85 * before the test as in the previous example. The second part applies 86 * a different modulus and also uses negation, thus it matches all 87 * numbers _not_ in 12, 13, 14, 112, 113, 114, 212, 213, 214... 88 * </p> 89 * <p> 90 * Syntax:<pre> 91 * \code 92 * rules = rule (';' rule)* 93 * rule = keyword ':' condition 94 * keyword = <identifier> 95 * condition = and_condition ('or' and_condition)* 96 * and_condition = relation ('and' relation)* 97 * relation = is_relation | in_relation | within_relation | 'n' <EOL> 98 * is_relation = expr 'is' ('not')? value 99 * in_relation = expr ('not')? 'in' range_list 100 * within_relation = expr ('not')? 'within' range 101 * expr = ('n' | 'i' | 'f' | 'v' | 'j') ('mod' value)? 102 * range_list = (range | value) (',' range_list)* 103 * value = digit+ ('.' digit+)? 104 * digit = 0|1|2|3|4|5|6|7|8|9 105 * range = value'..'value 106 * \endcode 107 * </pre></p> 108 * <p> 109 * <p> 110 * The i, f, and v values are defined as follows: 111 * </p> 112 * <ul> 113 * <li>i to be the integer digits.</li> 114 * <li>f to be the visible fractional digits, as an integer.</li> 115 * <li>v to be the number of visible fraction digits.</li> 116 * <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> 117 * </ul> 118 * <p> 119 * Examples are in the following table: 120 * </p> 121 * <table border='1' style="border-collapse:collapse"> 122 * <tbody> 123 * <tr> 124 * <th>n</th> 125 * <th>i</th> 126 * <th>f</th> 127 * <th>v</th> 128 * </tr> 129 * <tr> 130 * <td>1.0</td> 131 * <td>1</td> 132 * <td align="right">0</td> 133 * <td>1</td> 134 * </tr> 135 * <tr> 136 * <td>1.00</td> 137 * <td>1</td> 138 * <td align="right">0</td> 139 * <td>2</td> 140 * </tr> 141 * <tr> 142 * <td>1.3</td> 143 * <td>1</td> 144 * <td align="right">3</td> 145 * <td>1</td> 146 * </tr> 147 * <tr> 148 * <td>1.03</td> 149 * <td>1</td> 150 * <td align="right">3</td> 151 * <td>2</td> 152 * </tr> 153 * <tr> 154 * <td>1.23</td> 155 * <td>1</td> 156 * <td align="right">23</td> 157 * <td>2</td> 158 * </tr> 159 * </tbody> 160 * </table> 161 * <p> 162 * The difference between 'in' and 'within' is that 'in' only includes integers in the specified range, while 'within' 163 * includes all values. Using 'within' with a range_list consisting entirely of values is the same as using 'in' (it's 164 * not an error). 165 * </p> 166 167 * An "identifier" is a sequence of characters that do not have the 168 * Unicode Pattern_Syntax or Pattern_White_Space properties. 169 * <p> 170 * The difference between 'in' and 'within' is that 'in' only includes 171 * integers in the specified range, while 'within' includes all values. 172 * Using 'within' with a range_list consisting entirely of values is the 173 * same as using 'in' (it's not an error). 174 *</p> 175 * <p> 176 * Keywords 177 * could be defined by users or from ICU locale data. There are 6 178 * predefined values in ICU - 'zero', 'one', 'two', 'few', 'many' and 179 * 'other'. Callers need to check the value of keyword returned by 180 * {@link #select} method. 181 * </p> 182 * 183 * Examples:<pre> 184 * UnicodeString keyword = pl->select(number); 185 * if (keyword== UnicodeString("one") { 186 * ... 187 * } 188 * else if ( ... ) 189 * </pre> 190 * <strong>Note:</strong><br> 191 * <p> 192 * ICU defines plural rules for many locales based on CLDR <i>Language Plural Rules</i>. 193 * For these predefined rules, see CLDR page at 194 * http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html 195 * </p> 196 */ 197 class U_I18N_API PluralRules : public UObject { 198 public: 199 200 /** 201 * Constructor. 202 * @param status Output param set to success/failure code on exit, which 203 * must not indicate a failure before the function call. 204 * 205 * @stable ICU 4.0 206 */ 207 PluralRules(UErrorCode& status); 208 209 /** 210 * Copy constructor. 211 * @stable ICU 4.0 212 */ 213 PluralRules(const PluralRules& other); 214 215 /** 216 * Destructor. 217 * @stable ICU 4.0 218 */ 219 virtual ~PluralRules(); 220 221 /** 222 * Clone 223 * @stable ICU 4.0 224 */ 225 PluralRules* clone() const; 226 227 /** 228 * Assignment operator. 229 * @stable ICU 4.0 230 */ 231 PluralRules& operator=(const PluralRules&); 232 233 /** 234 * Creates a PluralRules from a description if it is parsable, otherwise 235 * returns NULL. 236 * 237 * @param description rule description 238 * @param status Output param set to success/failure code on exit, which 239 * must not indicate a failure before the function call. 240 * @return new PluralRules pointer. NULL if there is an error. 241 * @stable ICU 4.0 242 */ 243 static PluralRules* U_EXPORT2 createRules(const UnicodeString& description, 244 UErrorCode& status); 245 246 /** 247 * The default rules that accept any number. 248 * 249 * @param status Output param set to success/failure code on exit, which 250 * must not indicate a failure before the function call. 251 * @return new PluralRules pointer. NULL if there is an error. 252 * @stable ICU 4.0 253 */ 254 static PluralRules* U_EXPORT2 createDefaultRules(UErrorCode& status); 255 256 /** 257 * Provides access to the predefined cardinal-number <code>PluralRules</code> for a given 258 * locale. 259 * Same as forLocale(locale, UPLURAL_TYPE_CARDINAL, status). 260 * 261 * @param locale The locale for which a <code>PluralRules</code> object is 262 * returned. 263 * @param status Output param set to success/failure code on exit, which 264 * must not indicate a failure before the function call. 265 * @return The predefined <code>PluralRules</code> object pointer for 266 * this locale. If there's no predefined rules for this locale, 267 * the rules for the closest parent in the locale hierarchy 268 * that has one will be returned. The final fallback always 269 * returns the default 'other' rules. 270 * @stable ICU 4.0 271 */ 272 static PluralRules* U_EXPORT2 forLocale(const Locale& locale, UErrorCode& status); 273 274 /** 275 * Provides access to the predefined <code>PluralRules</code> for a given 276 * locale and the plural type. 277 * 278 * @param locale The locale for which a <code>PluralRules</code> object is 279 * returned. 280 * @param type The plural type (e.g., cardinal or ordinal). 281 * @param status Output param set to success/failure code on exit, which 282 * must not indicate a failure before the function call. 283 * @return The predefined <code>PluralRules</code> object pointer for 284 * this locale. If there's no predefined rules for this locale, 285 * the rules for the closest parent in the locale hierarchy 286 * that has one will be returned. The final fallback always 287 * returns the default 'other' rules. 288 * @stable ICU 50 289 */ 290 static PluralRules* U_EXPORT2 forLocale(const Locale& locale, UPluralType type, UErrorCode& status); 291 292 #ifndef U_HIDE_INTERNAL_API 293 /** 294 * Return a StringEnumeration over the locales for which there is plurals data. 295 * @return a StringEnumeration over the locales available. 296 * @internal 297 */ 298 static StringEnumeration* U_EXPORT2 getAvailableLocales(UErrorCode &status); 299 300 /** 301 * Returns whether or not there are overrides. 302 * @param locale the locale to check. 303 * @return 304 * @internal 305 */ 306 static UBool hasOverride(const Locale &locale); 307 308 /** 309 * For ICU use only. 310 * creates a SharedPluralRules object 311 * @internal 312 */ 313 static PluralRules* U_EXPORT2 internalForLocale(const Locale& locale, UPluralType type, UErrorCode& status); 314 315 /** 316 * For ICU use only. 317 * Returns handle to the shared, cached PluralRules instance. 318 * Caller must call removeRef() on returned value once it is done with 319 * the shared instance. 320 * @internal 321 */ 322 static const SharedPluralRules* U_EXPORT2 createSharedInstance( 323 const Locale& locale, UPluralType type, UErrorCode& status); 324 325 326 #endif /* U_HIDE_INTERNAL_API */ 327 328 /** 329 * Given a number, returns the keyword of the first rule that applies to 330 * the number. This function can be used with isKeyword* functions to 331 * determine the keyword for default plural rules. 332 * 333 * @param number The number for which the rule has to be determined. 334 * @return The keyword of the selected rule. 335 * @stable ICU 4.0 336 */ 337 UnicodeString select(int32_t number) const; 338 339 /** 340 * Given a number, returns the keyword of the first rule that applies to 341 * the number. This function can be used with isKeyword* functions to 342 * determine the keyword for default plural rules. 343 * 344 * @param number The number for which the rule has to be determined. 345 * @return The keyword of the selected rule. 346 * @stable ICU 4.0 347 */ 348 UnicodeString select(double number) const; 349 350 #ifndef U_HIDE_INTERNAL_API 351 /** 352 * Given a number and a format, returns the keyword of the first applicable 353 * rule for this PluralRules object. 354 * Note: This internal preview interface may be removed in the future if 355 * an architecturally cleaner solution reaches stable status. 356 * @param obj The numeric object for which the rule should be determined. 357 * @param fmt The NumberFormat specifying how the number will be formatted 358 * (this can affect the plural form, e.g. "1 dollar" vs "1.0 dollars"). 359 * @param status Input/output parameter. If at entry this indicates a 360 * failure status, the method returns immediately; otherwise 361 * this is set to indicate the outcome of the call. 362 * @return The keyword of the selected rule. Undefined in the case of an error. 363 * @internal ICU 59 technology preview, may be removed in the future 364 */ 365 UnicodeString select(const Formattable& obj, const NumberFormat& fmt, UErrorCode& status) const; 366 367 /** 368 * @internal 369 */ 370 UnicodeString select(const IFixedDecimal &number) const; 371 /** 372 * @internal 373 */ 374 UnicodeString select(const VisibleDigitsWithExponent &number) const; 375 #endif /* U_HIDE_INTERNAL_API */ 376 377 /** 378 * Returns a list of all rule keywords used in this <code>PluralRules</code> 379 * object. The rule 'other' is always present by default. 380 * 381 * @param status Output param set to success/failure code on exit, which 382 * must not indicate a failure before the function call. 383 * @return StringEnumeration with the keywords. 384 * The caller must delete the object. 385 * @stable ICU 4.0 386 */ 387 StringEnumeration* getKeywords(UErrorCode& status) const; 388 389 #ifndef U_HIDE_DEPRECATED_API 390 /** 391 * Deprecated Function, does not return useful results. 392 * 393 * Originally intended to return a unique value for this keyword if it exists, 394 * else the constant UPLRULES_NO_UNIQUE_VALUE. 395 * 396 * @param keyword The keyword. 397 * @return Stub deprecated function returns UPLRULES_NO_UNIQUE_VALUE always. 398 * @deprecated ICU 55 399 */ 400 double getUniqueKeywordValue(const UnicodeString& keyword); 401 402 /** 403 * Deprecated Function, does not produce useful results. 404 * 405 * Originally intended to return all the values for which select() would return the keyword. 406 * If the keyword is unknown, returns no values, but this is not an error. If 407 * the number of values is unlimited, returns no values and -1 as the 408 * count. 409 * 410 * The number of returned values is typically small. 411 * 412 * @param keyword The keyword. 413 * @param dest Array into which to put the returned values. May 414 * be NULL if destCapacity is 0. 415 * @param destCapacity The capacity of the array, must be at least 0. 416 * @param status The error code. Deprecated function, always sets U_UNSUPPORTED_ERROR. 417 * @return The count of values available, or -1. This count 418 * can be larger than destCapacity, but no more than 419 * destCapacity values will be written. 420 * @deprecated ICU 55 421 */ 422 int32_t getAllKeywordValues(const UnicodeString &keyword, 423 double *dest, int32_t destCapacity, 424 UErrorCode& status); 425 #endif /* U_HIDE_DEPRECATED_API */ 426 427 /** 428 * Returns sample values for which select() would return the keyword. If 429 * the keyword is unknown, returns no values, but this is not an error. 430 * 431 * The number of returned values is typically small. 432 * 433 * @param keyword The keyword. 434 * @param dest Array into which to put the returned values. May 435 * be NULL if destCapacity is 0. 436 * @param destCapacity The capacity of the array, must be at least 0. 437 * @param status The error code. 438 * @return The count of values written. 439 * If more than destCapacity samples are available, then 440 * only destCapacity are written, and destCapacity is returned as the count, 441 * rather than setting a U_BUFFER_OVERFLOW_ERROR. 442 * (The actual number of keyword values could be unlimited.) 443 * @stable ICU 4.8 444 */ 445 int32_t getSamples(const UnicodeString &keyword, 446 double *dest, int32_t destCapacity, 447 UErrorCode& status); 448 449 /** 450 * Returns TRUE if the given keyword is defined in this 451 * <code>PluralRules</code> object. 452 * 453 * @param keyword the input keyword. 454 * @return TRUE if the input keyword is defined. 455 * Otherwise, return FALSE. 456 * @stable ICU 4.0 457 */ 458 UBool isKeyword(const UnicodeString& keyword) const; 459 460 461 /** 462 * Returns keyword for default plural form. 463 * 464 * @return keyword for default plural form. 465 * @stable ICU 4.0 466 */ 467 UnicodeString getKeywordOther() const; 468 469 #ifndef U_HIDE_INTERNAL_API 470 /** 471 * 472 * @internal 473 */ 474 UnicodeString getRules() const; 475 #endif /* U_HIDE_INTERNAL_API */ 476 477 /** 478 * Compares the equality of two PluralRules objects. 479 * 480 * @param other The other PluralRules object to be compared with. 481 * @return True if the given PluralRules is the same as this 482 * PluralRules; false otherwise. 483 * @stable ICU 4.0 484 */ 485 virtual UBool operator==(const PluralRules& other) const; 486 487 /** 488 * Compares the inequality of two PluralRules objects. 489 * 490 * @param other The PluralRules object to be compared with. 491 * @return True if the given PluralRules is not the same as this 492 * PluralRules; false otherwise. 493 * @stable ICU 4.0 494 */ 495 UBool operator!=(const PluralRules& other) const {return !operator==(other);} 496 497 498 /** 499 * ICU "poor man's RTTI", returns a UClassID for this class. 500 * 501 * @stable ICU 4.0 502 * 503 */ 504 static UClassID U_EXPORT2 getStaticClassID(void); 505 506 /** 507 * ICU "poor man's RTTI", returns a UClassID for the actual class. 508 * 509 * @stable ICU 4.0 510 */ 511 virtual UClassID getDynamicClassID() const; 512 513 514 private: 515 RuleChain *mRules; 516 517 PluralRules(); // default constructor not implemented 518 void parseDescription(const UnicodeString& ruleData, UErrorCode &status); 519 int32_t getNumberValue(const UnicodeString& token) const; 520 UnicodeString getRuleFromResource(const Locale& locale, UPluralType type, UErrorCode& status); 521 RuleChain *rulesForKeyword(const UnicodeString &keyword) const; 522 523 friend class PluralRuleParser; 524 }; 525 526 U_NAMESPACE_END 527 528 #endif /* #if !UCONFIG_NO_FORMATTING */ 529 530 #endif // _PLURRULE 531 //eof 532