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