1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4*****************************************************************************************
5* Copyright (C) 2013-2014, International Business Machines
6* Corporation and others. All Rights Reserved.
7*****************************************************************************************
8*/
9
10#ifndef UNUMSYS_H
11#define UNUMSYS_H
12
13#include "unicode/utypes.h"
14
15#if !UCONFIG_NO_FORMATTING
16
17#include "unicode/uenum.h"
18#include "unicode/localpointer.h"
19
20/**
21 * \file
22 * \brief C API: UNumberingSystem, information about numbering systems
23 *
24 * Defines numbering systems. A numbering system describes the scheme by which
25 * numbers are to be presented to the end user. In its simplest form, a numbering
26 * system describes the set of digit characters that are to be used to display
27 * numbers, such as Western digits, Thai digits, Arabic-Indic digits, etc., in a
28 * positional numbering system with a specified radix (typically 10).
29 * More complicated numbering systems are algorithmic in nature, and require use
30 * of an RBNF formatter (rule based number formatter), in order to calculate
31 * the characters to be displayed for a given number. Examples of algorithmic
32 * numbering systems include Roman numerals, Chinese numerals, and Hebrew numerals.
33 * Formatting rules for many commonly used numbering systems are included in
34 * the ICU package, based on the numbering system rules defined in CLDR.
35 * Alternate numbering systems can be specified to a locale by using the
36 * numbers locale keyword.
37 */
38
39/**
40 * Opaque UNumberingSystem object for use in C programs.
41 * @stable ICU 52
42 */
43struct UNumberingSystem;
44typedef struct UNumberingSystem UNumberingSystem; /**< C typedef for struct UNumberingSystem. @stable ICU 52 */
45
46/**
47 * Opens a UNumberingSystem object using the default numbering system for the specified
48 * locale.
49 * @param locale The locale for which the default numbering system should be opened.
50 * @param status A pointer to a UErrorCode to receive any errors. For example, this
51 * may be U_UNSUPPORTED_ERROR for a locale such as "en@numbers=xyz" that
52 * specifies a numbering system unknown to ICU.
53 * @return A UNumberingSystem for the specified locale, or NULL if an error
54 * occurred.
55 * @stable ICU 52
56 */
57U_STABLE UNumberingSystem * U_EXPORT2
58unumsys_open(const char *locale, UErrorCode *status);
59
60/**
61 * Opens a UNumberingSystem object using the name of one of the predefined numbering
62 * systems specified by CLDR and known to ICU, such as "latn", "arabext", or "hanidec";
63 * the full list is returned by unumsys_openAvailableNames. Note that some of the names
64 * listed at http://unicode.org/repos/cldr/tags/latest/common/bcp47/number.xml - e.g.
65 * default, native, traditional, finance - do not identify specific numbering systems,
66 * but rather key values that may only be used as part of a locale, which in turn
67 * defines how they are mapped to a specific numbering system such as "latn" or "hant".
68 *
69 * @param name The name of the numbering system for which a UNumberingSystem object
70 * should be opened.
71 * @param status A pointer to a UErrorCode to receive any errors. For example, this
72 * may be U_UNSUPPORTED_ERROR for a numbering system such as "xyz" that
73 * is unknown to ICU.
74 * @return A UNumberingSystem for the specified name, or NULL if an error
75 * occurred.
76 * @stable ICU 52
77 */
78U_STABLE UNumberingSystem * U_EXPORT2
79unumsys_openByName(const char *name, UErrorCode *status);
80
81/**
82 * Close a UNumberingSystem object. Once closed it may no longer be used.
83 * @param unumsys The UNumberingSystem object to close.
84 * @stable ICU 52
85 */
86U_STABLE void U_EXPORT2
87unumsys_close(UNumberingSystem *unumsys);
88
89#if U_SHOW_CPLUSPLUS_API
90U_NAMESPACE_BEGIN
91
92/**
93 * \class LocalUNumberingSystemPointer
94 * "Smart pointer" class, closes a UNumberingSystem via unumsys_close().
95 * For most methods see the LocalPointerBase base class.
96 * @see LocalPointerBase
97 * @see LocalPointer
98 * @stable ICU 52
99 */
100U_DEFINE_LOCAL_OPEN_POINTER(LocalUNumberingSystemPointer, UNumberingSystem, unumsys_close);
101
102U_NAMESPACE_END
103#endif
104
105/**
106 * Returns an enumeration over the names of all of the predefined numbering systems known
107 * to ICU.
108 * @param status A pointer to a UErrorCode to receive any errors.
109 * @return A pointer to a UEnumeration that must be closed with uenum_close(),
110 * or NULL if an error occurred.
111 * @stable ICU 52
112 */
113U_STABLE UEnumeration * U_EXPORT2
114unumsys_openAvailableNames(UErrorCode *status);
115
116/**
117 * Returns the name of the specified UNumberingSystem object (if it is one of the
118 * predefined names known to ICU).
119 * @param unumsys The UNumberingSystem whose name is desired.
120 * @return A pointer to the name of the specified UNumberingSystem object, or
121 * NULL if the name is not one of the ICU predefined names. The pointer
122 * is only valid for the lifetime of the UNumberingSystem object.
123 * @stable ICU 52
124 */
125U_STABLE const char * U_EXPORT2
126unumsys_getName(const UNumberingSystem *unumsys);
127
128/**
129 * Returns whether the given UNumberingSystem object is for an algorithmic (not purely
130 * positional) system.
131 * @param unumsys The UNumberingSystem whose algorithmic status is desired.
132 * @return TRUE if the specified UNumberingSystem object is for an algorithmic
133 * system.
134 * @stable ICU 52
135 */
136U_STABLE UBool U_EXPORT2
137unumsys_isAlgorithmic(const UNumberingSystem *unumsys);
138
139/**
140 * Returns the radix of the specified UNumberingSystem object. Simple positional
141 * numbering systems typically have radix 10, but might have a radix of e.g. 16 for
142 * hexadecimal. The radix is less well-defined for non-positional algorithmic systems.
143 * @param unumsys The UNumberingSystem whose radix is desired.
144 * @return The radix of the specified UNumberingSystem object.
145 * @stable ICU 52
146 */
147U_STABLE int32_t U_EXPORT2
148unumsys_getRadix(const UNumberingSystem *unumsys);
149
150/**
151 * Get the description string of the specified UNumberingSystem object. For simple
152 * positional systems this is the ordered string of digits (with length matching
153 * the radix), e.g. "\u3007\u4E00\u4E8C\u4E09\u56DB\u4E94\u516D\u4E03\u516B\u4E5D"
154 * for "hanidec"; it would be "0123456789ABCDEF" for hexadecimal. For
155 * algorithmic systems this is the name of the RBNF ruleset used for formatting,
156 * e.g. "zh/SpelloutRules/%spellout-cardinal" for "hans" or "%greek-upper" for
157 * "grek".
158 * @param unumsys The UNumberingSystem whose description string is desired.
159 * @param result A pointer to a buffer to receive the description string.
160 * @param resultLength The maximum size of result.
161 * @param status A pointer to a UErrorCode to receive any errors.
162 * @return The total buffer size needed; if greater than resultLength, the
163 * output was truncated.
164 * @stable ICU 52
165 */
166U_STABLE int32_t U_EXPORT2
167unumsys_getDescription(const UNumberingSystem *unumsys, UChar *result,
168 int32_t resultLength, UErrorCode *status);
169
170#endif /* #if !UCONFIG_NO_FORMATTING */
171
172#endif
173