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/localpointer.h"
18#include "unicode/uenum.h"
19#ifndef U_HIDE_INTERNAL_API
20#include "unicode/unum.h"
21#endif /* U_HIDE_INTERNAL_API */
22
23/**
24 * \file
25 * \brief C API: Plural rules, select plural keywords for numeric values.
26 *
27 * A UPluralRules object defines rules for mapping non-negative numeric
28 * values onto a small set of keywords. Rules are constructed from a text
29 * description, consisting of a series of keywords and conditions.
30 * The uplrules_select function examines each condition in order and
31 * returns the keyword for the first condition that matches the number.
32 * If none match, the default rule(other) is returned.
33 *
34 * For more information, see the LDML spec, C.11 Language Plural Rules:
35 * http://www.unicode.org/reports/tr35/#Language_Plural_Rules
36 *
37 * Keywords: ICU locale data has 6 predefined values -
38 * 'zero', 'one', 'two', 'few', 'many' and 'other'. Callers need to check
39 * the value of keyword returned by the uplrules_select function.
40 *
41 * These are based on CLDR <i>Language Plural Rules</i>. For these
42 * predefined rules, see the CLDR page at
43 * http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html
44 */
45
46/**
47 * Type of plurals and PluralRules.
48 * @stable ICU 50
49 */
50enum UPluralType {
51 /**
52 * Plural rules for cardinal numbers: 1 file vs. 2 files.
53 * @stable ICU 50
54 */
55 UPLURAL_TYPE_CARDINAL,
56 /**
57 * Plural rules for ordinal numbers: 1st file, 2nd file, 3rd file, 4th file, etc.
58 * @stable ICU 50
59 */
60 UPLURAL_TYPE_ORDINAL,
61#ifndef U_HIDE_DEPRECATED_API
62 /**
63 * One more than the highest normal UPluralType value.
64 * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
65 */
66 UPLURAL_TYPE_COUNT
67#endif /* U_HIDE_DEPRECATED_API */
68};
69/**
70 * @stable ICU 50
71 */
72typedef enum UPluralType UPluralType;
73
74/**
75 * Opaque UPluralRules object for use in C programs.
76 * @stable ICU 4.8
77 */
78struct UPluralRules;
79typedef struct UPluralRules UPluralRules; /**< C typedef for struct UPluralRules. @stable ICU 4.8 */
80
81/**
82 * Opens a new UPluralRules object using the predefined cardinal-number plural rules for a
83 * given locale.
84 * Same as uplrules_openForType(locale, UPLURAL_TYPE_CARDINAL, status).
85 * @param locale The locale for which the rules are desired.
86 * @param status A pointer to a UErrorCode to receive any errors.
87 * @return A UPluralRules for the specified locale, or NULL if an error occurred.
88 * @stable ICU 4.8
89 */
90U_CAPI UPluralRules* U_EXPORT2
91uplrules_open(const char *locale, UErrorCode *status);
92
93/**
94 * Opens a new UPluralRules object using the predefined plural rules for a
95 * given locale and the plural type.
96 * @param locale The locale for which the rules are desired.
97 * @param type The plural type (e.g., cardinal or ordinal).
98 * @param status A pointer to a UErrorCode to receive any errors.
99 * @return A UPluralRules for the specified locale, or NULL if an error occurred.
100 * @stable ICU 50
101 */
102U_CAPI UPluralRules* U_EXPORT2
103uplrules_openForType(const char *locale, UPluralType type, UErrorCode *status);
104
105/**
106 * Closes a UPluralRules object. Once closed it may no longer be used.
107 * @param uplrules The UPluralRules object to close.
108 * @stable ICU 4.8
109 */
110U_CAPI void U_EXPORT2
111uplrules_close(UPluralRules *uplrules);
112
113
114#if U_SHOW_CPLUSPLUS_API
115
116U_NAMESPACE_BEGIN
117
118/**
119 * \class LocalUPluralRulesPointer
120 * "Smart pointer" class, closes a UPluralRules via uplrules_close().
121 * For most methods see the LocalPointerBase base class.
122 *
123 * @see LocalPointerBase
124 * @see LocalPointer
125 * @stable ICU 4.8
126 */
127U_DEFINE_LOCAL_OPEN_POINTER(LocalUPluralRulesPointer, UPluralRules, uplrules_close);
128
129U_NAMESPACE_END
130
131#endif
132
133
134/**
135 * Given a number, returns the keyword of the first rule that
136 * applies to the number, according to the supplied UPluralRules object.
137 * @param uplrules The UPluralRules object specifying the rules.
138 * @param number The number for which the rule has to be determined.
139 * @param keyword The keyword of the rule that applies to number.
140 * @param capacity The capacity of keyword.
141 * @param status A pointer to a UErrorCode to receive any errors.
142 * @return The length of keyword.
143 * @stable ICU 4.8
144 */
145U_CAPI int32_t U_EXPORT2
146uplrules_select(const UPluralRules *uplrules,
147 double number,
148 UChar *keyword, int32_t capacity,
149 UErrorCode *status);
150
151#ifndef U_HIDE_INTERNAL_API
152/**
153 * Given a number, returns the keyword of the first rule that applies to the
154 * number, according to the UPluralRules object and given the number format
155 * specified by the UNumberFormat object.
156 * Note: This internal preview interface may be removed in the future if
157 * an architecturally cleaner solution reaches stable status.
158 * @param uplrules The UPluralRules object specifying the rules.
159 * @param number The number for which the rule has to be determined.
160 * @param fmt The UNumberFormat specifying how the number will be formatted
161 * (this can affect the plural form, e.g. "1 dollar" vs "1.0 dollars").
162 * If this is NULL, the function behaves like uplrules_select.
163 * @param keyword The keyword of the rule that applies to number.
164 * @param capacity The capacity of the keyword buffer.
165 * @param status A pointer to a UErrorCode to receive any errors.
166 * @return The length of keyword.
167 * @internal ICU 59 technology preview, may be removed in the future
168 */
169U_INTERNAL int32_t U_EXPORT2
170uplrules_selectWithFormat(const UPluralRules *uplrules,
171 double number,
172 const UNumberFormat *fmt,
173 UChar *keyword, int32_t capacity,
174 UErrorCode *status);
175
176#endif /* U_HIDE_INTERNAL_API */
177
178/**
179 * Creates a string enumeration of all plural rule keywords used in this
180 * UPluralRules object. The rule "other" is always present by default.
181 * @param uplrules The UPluralRules object specifying the rules for
182 * a given locale.
183 * @param status A pointer to a UErrorCode to receive any errors.
184 * @return a string enumeration over plural rule keywords, or NULL
185 * upon error. The caller is responsible for closing the result.
186 * @stable ICU 59
187 */
188U_STABLE UEnumeration* U_EXPORT2
189uplrules_getKeywords(const UPluralRules *uplrules,
190 UErrorCode *status);
191
192#endif /* #if !UCONFIG_NO_FORMATTING */
193
194#endif
195