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diff --git a/intl/icu/source/i18n/unicode/msgfmt.h b/intl/icu/source/i18n/unicode/msgfmt.h new file mode 100644 index 0000000000..a8a61f90e3 --- /dev/null +++ b/intl/icu/source/i18n/unicode/msgfmt.h @@ -0,0 +1,1117 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +* Copyright (C) 2007-2013, International Business Machines Corporation and +* others. All Rights Reserved. +******************************************************************************** +* +* File MSGFMT.H +* +* Modification History: +* +* Date Name Description +* 02/19/97 aliu Converted from java. +* 03/20/97 helena Finished first cut of implementation. +* 07/22/98 stephen Removed operator!= (defined in Format) +* 08/19/2002 srl Removing Javaisms +*******************************************************************************/ + +#ifndef MSGFMT_H +#define MSGFMT_H + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API + +/** + * \file + * \brief C++ API: Formats messages in a language-neutral way. + */ + +#if !UCONFIG_NO_FORMATTING + +#include "unicode/format.h" +#include "unicode/locid.h" +#include "unicode/messagepattern.h" +#include "unicode/parseerr.h" +#include "unicode/plurfmt.h" +#include "unicode/plurrule.h" + +U_CDECL_BEGIN +// Forward declaration. +struct UHashtable; +typedef struct UHashtable UHashtable; /**< @internal */ +U_CDECL_END + +U_NAMESPACE_BEGIN + +class AppendableWrapper; +class DateFormat; +class NumberFormat; + +/** + * <p>MessageFormat prepares strings for display to users, + * with optional arguments (variables/placeholders). + * The arguments can occur in any order, which is necessary for translation + * into languages with different grammars. + * + * <p>A MessageFormat is constructed from a <em>pattern</em> string + * with arguments in {curly braces} which will be replaced by formatted values. + * + * <p><code>MessageFormat</code> differs from the other <code>Format</code> + * classes in that you create a <code>MessageFormat</code> object with one + * of its constructors (not with a <code>createInstance</code> style factory + * method). Factory methods aren't necessary because <code>MessageFormat</code> + * itself doesn't implement locale-specific behavior. Any locale-specific + * behavior is defined by the pattern that you provide and the + * subformats used for inserted arguments. + * + * <p>Arguments can be named (using identifiers) or numbered (using small ASCII-digit integers). + * Some of the API methods work only with argument numbers and throw an exception + * if the pattern has named arguments (see {@link #usesNamedArguments()}). + * + * <p>An argument might not specify any format type. In this case, + * a numeric value is formatted with a default (for the locale) NumberFormat, + * and a date/time value is formatted with a default (for the locale) DateFormat. + * + * <p>An argument might specify a "simple" type for which the specified + * Format object is created, cached and used. + * + * <p>An argument might have a "complex" type with nested MessageFormat sub-patterns. + * During formatting, one of these sub-messages is selected according to the argument value + * and recursively formatted. + * + * <p>After construction, a custom Format object can be set for + * a top-level argument, overriding the default formatting and parsing behavior + * for that argument. + * However, custom formatting can be achieved more simply by writing + * a typeless argument in the pattern string + * and supplying it with a preformatted string value. + * + * <p>When formatting, MessageFormat takes a collection of argument values + * and writes an output string. + * The argument values may be passed as an array + * (when the pattern contains only numbered arguments) + * or as an array of names and and an array of arguments (which works for both named + * and numbered arguments). + * + * <p>Each argument is matched with one of the input values by array index or argument name + * and formatted according to its pattern specification + * (or using a custom Format object if one was set). + * A numbered pattern argument is matched with an argument name that contains that number + * as an ASCII-decimal-digit string (without leading zero). + * + * <h4><a name="patterns">Patterns and Their Interpretation</a></h4> + * + * <code>MessageFormat</code> uses patterns of the following form: + * <pre> + * message = messageText (argument messageText)* + * argument = noneArg | simpleArg | complexArg + * complexArg = choiceArg | pluralArg | selectArg | selectordinalArg + * + * noneArg = '{' argNameOrNumber '}' + * simpleArg = '{' argNameOrNumber ',' argType [',' argStyle] '}' + * choiceArg = '{' argNameOrNumber ',' "choice" ',' choiceStyle '}' + * pluralArg = '{' argNameOrNumber ',' "plural" ',' pluralStyle '}' + * selectArg = '{' argNameOrNumber ',' "select" ',' selectStyle '}' + * selectordinalArg = '{' argNameOrNumber ',' "selectordinal" ',' pluralStyle '}' + * + * choiceStyle: see {@link ChoiceFormat} + * pluralStyle: see {@link PluralFormat} + * selectStyle: see {@link SelectFormat} + * + * argNameOrNumber = argName | argNumber + * argName = [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+ + * argNumber = '0' | ('1'..'9' ('0'..'9')*) + * + * argType = "number" | "date" | "time" | "spellout" | "ordinal" | "duration" + * argStyle = "short" | "medium" | "long" | "full" | "integer" | "currency" | "percent" | argStyleText | "::" argSkeletonText + * </pre> + * + * <ul> + * <li>messageText can contain quoted literal strings including syntax characters. + * A quoted literal string begins with an ASCII apostrophe and a syntax character + * (usually a {curly brace}) and continues until the next single apostrophe. + * A double ASCII apostrophe inside or outside of a quoted string represents + * one literal apostrophe. + * <li>Quotable syntax characters are the {curly braces} in all messageText parts, + * plus the '#' sign in a messageText immediately inside a pluralStyle, + * and the '|' symbol in a messageText immediately inside a choiceStyle. + * <li>See also {@link #UMessagePatternApostropheMode} + * <li>In argStyleText, every single ASCII apostrophe begins and ends quoted literal text, + * and unquoted {curly braces} must occur in matched pairs. + * </ul> + * + * <p>Recommendation: Use the real apostrophe (single quote) character + * \htmlonly’\endhtmlonly (U+2019) for + * human-readable text, and use the ASCII apostrophe ' (U+0027) + * only in program syntax, like quoting in MessageFormat. + * See the annotations for U+0027 Apostrophe in The Unicode Standard. + * + * <p>The <code>choice</code> argument type is deprecated. + * Use <code>plural</code> arguments for proper plural selection, + * and <code>select</code> arguments for simple selection among a fixed set of choices. + * + * <p>The <code>argType</code> and <code>argStyle</code> values are used to create + * a <code>Format</code> instance for the format element. The following + * table shows how the values map to Format instances. Combinations not + * shown in the table are illegal. Any <code>argStyleText</code> must + * be a valid pattern string for the Format subclass used. + * + * <p><table border=1> + * <tr> + * <th>argType + * <th>argStyle + * <th>resulting Format object + * <tr> + * <td colspan=2><i>(none)</i> + * <td><code>null</code> + * <tr> + * <td rowspan=6><code>number</code> + * <td><i>(none)</i> + * <td><code>NumberFormat.createInstance(getLocale(), status)</code> + * <tr> + * <td><code>integer</code> + * <td><code>NumberFormat.createInstance(getLocale(), kNumberStyle, status)</code> + * <tr> + * <td><code>currency</code> + * <td><code>NumberFormat.createCurrencyInstance(getLocale(), status)</code> + * <tr> + * <td><code>percent</code> + * <td><code>NumberFormat.createPercentInstance(getLocale(), status)</code> + * <tr> + * <td><i>argStyleText</i> + * <td><code>new DecimalFormat(argStyleText, new DecimalFormatSymbols(getLocale(), status), status)</code> + * <tr> + * <td><i>argSkeletonText</i> + * <td><code>NumberFormatter::forSkeleton(argSkeletonText, status).locale(getLocale()).toFormat(status)</code> + * <tr> + * <td rowspan=7><code>date</code> + * <td><i>(none)</i> + * <td><code>DateFormat.createDateInstance(kDefault, getLocale(), status)</code> + * <tr> + * <td><code>short</code> + * <td><code>DateFormat.createDateInstance(kShort, getLocale(), status)</code> + * <tr> + * <td><code>medium</code> + * <td><code>DateFormat.createDateInstance(kDefault, getLocale(), status)</code> + * <tr> + * <td><code>long</code> + * <td><code>DateFormat.createDateInstance(kLong, getLocale(), status)</code> + * <tr> + * <td><code>full</code> + * <td><code>DateFormat.createDateInstance(kFull, getLocale(), status)</code> + * <tr> + * <td><i>argStyleText</i> + * <td><code>new SimpleDateFormat(argStyleText, getLocale(), status)</code> + * <tr> + * <td><i>argSkeletonText</i> + * <td><code>DateFormat::createInstanceForSkeleton(argSkeletonText, getLocale(), status)</code> + * <tr> + * <td rowspan=6><code>time</code> + * <td><i>(none)</i> + * <td><code>DateFormat.createTimeInstance(kDefault, getLocale(), status)</code> + * <tr> + * <td><code>short</code> + * <td><code>DateFormat.createTimeInstance(kShort, getLocale(), status)</code> + * <tr> + * <td><code>medium</code> + * <td><code>DateFormat.createTimeInstance(kDefault, getLocale(), status)</code> + * <tr> + * <td><code>long</code> + * <td><code>DateFormat.createTimeInstance(kLong, getLocale(), status)</code> + * <tr> + * <td><code>full</code> + * <td><code>DateFormat.createTimeInstance(kFull, getLocale(), status)</code> + * <tr> + * <td><i>argStyleText</i> + * <td><code>new SimpleDateFormat(argStyleText, getLocale(), status)</code> + * <tr> + * <td><code>spellout</code> + * <td><i>argStyleText (optional)</i> + * <td><code>new RuleBasedNumberFormat(URBNF_SPELLOUT, getLocale(), status) + * <br/> .setDefaultRuleset(argStyleText, status);</code> + * <tr> + * <td><code>ordinal</code> + * <td><i>argStyleText (optional)</i> + * <td><code>new RuleBasedNumberFormat(URBNF_ORDINAL, getLocale(), status) + * <br/> .setDefaultRuleset(argStyleText, status);</code> + * <tr> + * <td><code>duration</code> + * <td><i>argStyleText (optional)</i> + * <td><code>new RuleBasedNumberFormat(URBNF_DURATION, getLocale(), status) + * <br/> .setDefaultRuleset(argStyleText, status);</code> + * </table> + * <p> + * + * <h4>Argument formatting</h4> + * + * <p>Arguments are formatted according to their type, using the default + * ICU formatters for those types, unless otherwise specified.</p> + * + * <p>There are also several ways to control the formatting.</p> + * + * <p>We recommend you use default styles, predefined style values, skeletons, + * or preformatted values, but not pattern strings or custom format objects.</p> + * + * <p>For more details, see the + * <a href="https://unicode-org.github.io/icu/userguide/format_parse/messages">ICU User Guide</a>.</p> + * + * <h4>Usage Information</h4> + * + * <p>Here are some examples of usage: + * Example 1: + * + * <pre> + * \code + * UErrorCode success = U_ZERO_ERROR; + * GregorianCalendar cal(success); + * Formattable arguments[] = { + * 7L, + * Formattable( (Date) cal.getTime(success), Formattable::kIsDate), + * "a disturbance in the Force" + * }; + * + * UnicodeString result; + * MessageFormat::format( + * "At {1,time,::jmm} on {1,date,::dMMMM}, there was {2} on planet {0,number}.", + * arguments, 3, result, success ); + * + * cout << "result: " << result << endl; + * //<output>: At 4:34 PM on March 23, there was a disturbance + * // in the Force on planet 7. + * \endcode + * </pre> + * + * Typically, the message format will come from resources, and the + * arguments will be dynamically set at runtime. + * + * <p>Example 2: + * + * <pre> + * \code + * success = U_ZERO_ERROR; + * Formattable testArgs[] = {3L, "MyDisk"}; + * + * MessageFormat form( + * "The disk \"{1}\" contains {0} file(s).", success ); + * + * UnicodeString string; + * FieldPosition fpos = 0; + * cout << "format: " << form.format(testArgs, 2, string, fpos, success ) << endl; + * + * // output, with different testArgs: + * // output: The disk "MyDisk" contains 0 file(s). + * // output: The disk "MyDisk" contains 1 file(s). + * // output: The disk "MyDisk" contains 1,273 file(s). + * \endcode + * </pre> + * + * + * <p>For messages that include plural forms, you can use a plural argument: + * <pre> + * \code + * success = U_ZERO_ERROR; + * MessageFormat msgFmt( + * "{num_files, plural, " + * "=0{There are no files on disk \"{disk_name}\".}" + * "=1{There is one file on disk \"{disk_name}\".}" + * "other{There are # files on disk \"{disk_name}\".}}", + * Locale("en"), + * success); + * FieldPosition fpos = 0; + * Formattable testArgs[] = {0L, "MyDisk"}; + * UnicodeString testArgsNames[] = {"num_files", "disk_name"}; + * UnicodeString result; + * cout << msgFmt.format(testArgs, testArgsNames, 2, result, fpos, 0, success); + * testArgs[0] = 3L; + * cout << msgFmt.format(testArgs, testArgsNames, 2, result, fpos, 0, success); + * \endcode + * <em>output</em>: + * There are no files on disk "MyDisk". + * There are 3 files on "MyDisk". + * </pre> + * See {@link PluralFormat} and {@link PluralRules} for details. + * + * <h4><a name="synchronization">Synchronization</a></h4> + * + * <p>MessageFormats are not synchronized. + * It is recommended to create separate format instances for each thread. + * If multiple threads access a format concurrently, it must be synchronized + * externally. + * + * @stable ICU 2.0 + */ +class U_I18N_API MessageFormat : public Format { +public: +#ifndef U_HIDE_OBSOLETE_API + /** + * Enum type for kMaxFormat. + * @obsolete ICU 3.0. The 10-argument limit was removed as of ICU 2.6, + * rendering this enum type obsolete. + */ + enum EFormatNumber { + /** + * The maximum number of arguments. + * @obsolete ICU 3.0. The 10-argument limit was removed as of ICU 2.6, + * rendering this constant obsolete. + */ + kMaxFormat = 10 + }; +#endif /* U_HIDE_OBSOLETE_API */ + + /** + * Constructs a new MessageFormat using the given pattern and the + * default locale. + * + * @param pattern Pattern used to construct object. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 2.0 + */ + MessageFormat(const UnicodeString& pattern, + UErrorCode &status); + + /** + * Constructs a new MessageFormat using the given pattern and locale. + * @param pattern Pattern used to construct object. + * @param newLocale The locale to use for formatting dates and numbers. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 2.0 + */ + MessageFormat(const UnicodeString& pattern, + const Locale& newLocale, + UErrorCode& status); + /** + * Constructs a new MessageFormat using the given pattern and locale. + * @param pattern Pattern used to construct object. + * @param newLocale The locale to use for formatting dates and numbers. + * @param parseError Struct to receive information on the position + * of an error within the pattern. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 2.0 + */ + MessageFormat(const UnicodeString& pattern, + const Locale& newLocale, + UParseError& parseError, + UErrorCode& status); + /** + * Constructs a new MessageFormat from an existing one. + * @stable ICU 2.0 + */ + MessageFormat(const MessageFormat&); + + /** + * Assignment operator. + * @stable ICU 2.0 + */ + const MessageFormat& operator=(const MessageFormat&); + + /** + * Destructor. + * @stable ICU 2.0 + */ + virtual ~MessageFormat(); + + /** + * Clones this Format object polymorphically. The caller owns the + * result and should delete it when done. + * @stable ICU 2.0 + */ + virtual MessageFormat* clone() const override; + + /** + * Returns true if the given Format objects are semantically equal. + * Objects of different subclasses are considered unequal. + * @param other the object to be compared with. + * @return true if the given Format objects are semantically equal. + * @stable ICU 2.0 + */ + virtual bool operator==(const Format& other) const override; + + /** + * Sets the locale to be used for creating argument Format objects. + * @param theLocale the new locale value to be set. + * @stable ICU 2.0 + */ + virtual void setLocale(const Locale& theLocale); + + /** + * Gets the locale used for creating argument Format objects. + * format information. + * @return the locale of the object. + * @stable ICU 2.0 + */ + virtual const Locale& getLocale(void) const; + + /** + * Applies the given pattern string to this message format. + * + * @param pattern The pattern to be applied. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 2.0 + */ + virtual void applyPattern(const UnicodeString& pattern, + UErrorCode& status); + /** + * Applies the given pattern string to this message format. + * + * @param pattern The pattern to be applied. + * @param parseError Struct to receive information on the position + * of an error within the pattern. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 2.0 + */ + virtual void applyPattern(const UnicodeString& pattern, + UParseError& parseError, + UErrorCode& status); + + /** + * Sets the UMessagePatternApostropheMode and the pattern used by this message format. + * Parses the pattern and caches Format objects for simple argument types. + * Patterns and their interpretation are specified in the + * <a href="#patterns">class description</a>. + * <p> + * This method is best used only once on a given object to avoid confusion about the mode, + * and after constructing the object with an empty pattern string to minimize overhead. + * + * @param pattern The pattern to be applied. + * @param aposMode The new apostrophe mode. + * @param parseError Struct to receive information on the position + * of an error within the pattern. + * Can be nullptr. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @stable ICU 4.8 + */ + virtual void applyPattern(const UnicodeString& pattern, + UMessagePatternApostropheMode aposMode, + UParseError* parseError, + UErrorCode& status); + + /** + * @return this instance's UMessagePatternApostropheMode. + * @stable ICU 4.8 + */ + UMessagePatternApostropheMode getApostropheMode() const { + return msgPattern.getApostropheMode(); + } + + /** + * Returns a pattern that can be used to recreate this object. + * + * @param appendTo Output parameter to receive the pattern. + * Result is appended to existing contents. + * @return Reference to 'appendTo' parameter. + * @stable ICU 2.0 + */ + virtual UnicodeString& toPattern(UnicodeString& appendTo) const; + + /** + * Sets subformats. + * See the class description about format numbering. + * The caller should not delete the Format objects after this call. + * <EM>The array formatsToAdopt is not itself adopted.</EM> Its + * ownership is retained by the caller. If the call fails because + * memory cannot be allocated, then the formats will be deleted + * by this method, and this object will remain unchanged. + * + * <p>If this format uses named arguments, the new formats are discarded + * and this format remains unchanged. + * + * @stable ICU 2.0 + * @param formatsToAdopt the format to be adopted. + * @param count the size of the array. + */ + virtual void adoptFormats(Format** formatsToAdopt, int32_t count); + + /** + * Sets subformats. + * See the class description about format numbering. + * Each item in the array is cloned into the internal array. + * If the call fails because memory cannot be allocated, then this + * object will remain unchanged. + * + * <p>If this format uses named arguments, the new formats are discarded + * and this format remains unchanged. + * + * @stable ICU 2.0 + * @param newFormats the new format to be set. + * @param cnt the size of the array. + */ + virtual void setFormats(const Format** newFormats, int32_t cnt); + + + /** + * Sets one subformat. + * See the class description about format numbering. + * The caller should not delete the Format object after this call. + * If the number is over the number of formats already set, + * the item will be deleted and ignored. + * + * <p>If this format uses named arguments, the new format is discarded + * and this format remains unchanged. + * + * @stable ICU 2.0 + * @param formatNumber index of the subformat. + * @param formatToAdopt the format to be adopted. + */ + virtual void adoptFormat(int32_t formatNumber, Format* formatToAdopt); + + /** + * Sets one subformat. + * See the class description about format numbering. + * If the number is over the number of formats already set, + * the item will be ignored. + * @param formatNumber index of the subformat. + * @param format the format to be set. + * @stable ICU 2.0 + */ + virtual void setFormat(int32_t formatNumber, const Format& format); + + /** + * Gets format names. This function returns formatNames in StringEnumerations + * which can be used with getFormat() and setFormat() to export formattable + * array from current MessageFormat to another. It is the caller's responsibility + * to delete the returned formatNames. + * @param status output param set to success/failure code. + * @stable ICU 4.0 + */ + virtual StringEnumeration* getFormatNames(UErrorCode& status); + + /** + * Gets subformat pointer for given format name. + * This function supports both named and numbered + * arguments. If numbered, the formatName is the + * corresponding UnicodeStrings (e.g. "0", "1", "2"...). + * The returned Format object should not be deleted by the caller, + * nor should the pointer of other object . The pointer and its + * contents remain valid only until the next call to any method + * of this class is made with this object. + * @param formatName the name or number specifying a format + * @param status output param set to success/failure code. + * @stable ICU 4.0 + */ + virtual Format* getFormat(const UnicodeString& formatName, UErrorCode& status); + + /** + * Sets one subformat for given format name. + * See the class description about format name. + * This function supports both named and numbered + * arguments-- if numbered, the formatName is the + * corresponding UnicodeStrings (e.g. "0", "1", "2"...). + * If there is no matched formatName or wrong type, + * the item will be ignored. + * @param formatName Name of the subformat. + * @param format the format to be set. + * @param status output param set to success/failure code. + * @stable ICU 4.0 + */ + virtual void setFormat(const UnicodeString& formatName, const Format& format, UErrorCode& status); + + /** + * Sets one subformat for given format name. + * See the class description about format name. + * This function supports both named and numbered + * arguments-- if numbered, the formatName is the + * corresponding UnicodeStrings (e.g. "0", "1", "2"...). + * If there is no matched formatName or wrong type, + * the item will be ignored. + * The caller should not delete the Format object after this call. + * @param formatName Name of the subformat. + * @param formatToAdopt Format to be adopted. + * @param status output param set to success/failure code. + * @stable ICU 4.0 + */ + virtual void adoptFormat(const UnicodeString& formatName, Format* formatToAdopt, UErrorCode& status); + + /** + * Gets an array of subformats of this object. The returned array + * should not be deleted by the caller, nor should the pointers + * within the array. The array and its contents remain valid only + * until the next call to this format. See the class description + * about format numbering. + * + * @param count output parameter to receive the size of the array + * @return an array of count Format* objects, or nullptr if out of + * memory. Any or all of the array elements may be nullptr. + * @stable ICU 2.0 + */ + virtual const Format** getFormats(int32_t& count) const; + + + using Format::format; + + /** + * Formats the given array of arguments into a user-readable string. + * Does not take ownership of the Formattable* array or its contents. + * + * <p>If this format uses named arguments, appendTo is unchanged and + * status is set to U_ILLEGAL_ARGUMENT_ERROR. + * + * @param source An array of objects to be formatted. + * @param count The number of elements of 'source'. + * @param appendTo Output parameter to receive result. + * Result is appended to existing contents. + * @param ignore Not used; inherited from base class API. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @return Reference to 'appendTo' parameter. + * @stable ICU 2.0 + */ + UnicodeString& format(const Formattable* source, + int32_t count, + UnicodeString& appendTo, + FieldPosition& ignore, + UErrorCode& status) const; + + /** + * Formats the given array of arguments into a user-readable string + * using the given pattern. + * + * <p>If this format uses named arguments, appendTo is unchanged and + * status is set to U_ILLEGAL_ARGUMENT_ERROR. + * + * @param pattern The pattern. + * @param arguments An array of objects to be formatted. + * @param count The number of elements of 'source'. + * @param appendTo Output parameter to receive result. + * Result is appended to existing contents. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @return Reference to 'appendTo' parameter. + * @stable ICU 2.0 + */ + static UnicodeString& format(const UnicodeString& pattern, + const Formattable* arguments, + int32_t count, + UnicodeString& appendTo, + UErrorCode& status); + + /** + * Formats the given array of arguments into a user-readable + * string. The array must be stored within a single Formattable + * object of type kArray. If the Formattable object type is not of + * type kArray, then returns a failing UErrorCode. + * + * <p>If this format uses named arguments, appendTo is unchanged and + * status is set to U_ILLEGAL_ARGUMENT_ERROR. + * + * @param obj A Formattable of type kArray containing + * arguments to be formatted. + * @param appendTo Output parameter to receive result. + * Result is appended to existing contents. + * @param pos On input: an alignment field, if desired. + * On output: the offsets of the alignment field. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @return Reference to 'appendTo' parameter. + * @stable ICU 2.0 + */ + virtual UnicodeString& format(const Formattable& obj, + UnicodeString& appendTo, + FieldPosition& pos, + UErrorCode& status) const override; + + /** + * Formats the given array of arguments into a user-defined argument name + * array. This function supports both named and numbered + * arguments-- if numbered, the formatName is the + * corresponding UnicodeStrings (e.g. "0", "1", "2"...). + * + * @param argumentNames argument name array + * @param arguments An array of objects to be formatted. + * @param count The number of elements of 'argumentNames' and + * arguments. The number of argumentNames and arguments + * must be the same. + * @param appendTo Output parameter to receive result. + * Result is appended to existing contents. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @return Reference to 'appendTo' parameter. + * @stable ICU 4.0 + */ + UnicodeString& format(const UnicodeString* argumentNames, + const Formattable* arguments, + int32_t count, + UnicodeString& appendTo, + UErrorCode& status) const; + /** + * Parses the given string into an array of output arguments. + * + * @param source String to be parsed. + * @param pos On input, starting position for parse. On output, + * final position after parse. Unchanged if parse + * fails. + * @param count Output parameter to receive the number of arguments + * parsed. + * @return an array of parsed arguments. The caller owns both + * the array and its contents. + * @stable ICU 2.0 + */ + virtual Formattable* parse(const UnicodeString& source, + ParsePosition& pos, + int32_t& count) const; + + /** + * Parses the given string into an array of output arguments. + * + * <p>If this format uses named arguments, status is set to + * U_ARGUMENT_TYPE_MISMATCH. + * + * @param source String to be parsed. + * @param count Output param to receive size of returned array. + * @param status Input/output error code. If the + * pattern cannot be parsed, set to failure code. + * @return an array of parsed arguments. The caller owns both + * the array and its contents. Returns nullptr if status is not U_ZERO_ERROR. + * + * @stable ICU 2.0 + */ + virtual Formattable* parse(const UnicodeString& source, + int32_t& count, + UErrorCode& status) const; + + /** + * Parses the given string into an array of output arguments + * stored within a single Formattable of type kArray. + * + * @param source The string to be parsed into an object. + * @param result Formattable to be set to the parse result. + * If parse fails, return contents are undefined. + * @param pos On input, starting position for parse. On output, + * final position after parse. Unchanged if parse + * fails. + * @stable ICU 2.0 + */ + virtual void parseObject(const UnicodeString& source, + Formattable& result, + ParsePosition& pos) const override; + + /** + * Convert an 'apostrophe-friendly' pattern into a standard + * pattern. Standard patterns treat all apostrophes as + * quotes, which is problematic in some languages, e.g. + * French, where apostrophe is commonly used. This utility + * assumes that only an unpaired apostrophe immediately before + * a brace is a true quote. Other unpaired apostrophes are paired, + * and the resulting standard pattern string is returned. + * + * <p><b>Note</b> it is not guaranteed that the returned pattern + * is indeed a valid pattern. The only effect is to convert + * between patterns having different quoting semantics. + * + * @param pattern the 'apostrophe-friendly' patttern to convert + * @param status Input/output error code. If the pattern + * cannot be parsed, the failure code is set. + * @return the standard equivalent of the original pattern + * @stable ICU 3.4 + */ + static UnicodeString autoQuoteApostrophe(const UnicodeString& pattern, + UErrorCode& status); + + + /** + * Returns true if this MessageFormat uses named arguments, + * and false otherwise. See class description. + * + * @return true if named arguments are used. + * @stable ICU 4.0 + */ + UBool usesNamedArguments() const; + + +#ifndef U_HIDE_INTERNAL_API + /** + * This API is for ICU internal use only. + * Please do not use it. + * + * Returns argument types count in the parsed pattern. + * Used to distinguish pattern "{0} d" and "d". + * + * @return The number of formattable types in the pattern + * @internal + */ + int32_t getArgTypeCount() const; +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. + * This method is to implement a simple version of RTTI, since not all + * C++ compilers support genuine RTTI. Polymorphic operator==() and + * clone() methods call this method. + * + * @return The class ID for this object. All objects of a + * given class have the same class ID. Objects of + * other classes have different class IDs. + * @stable ICU 2.0 + */ + virtual UClassID getDynamicClassID(void) const override; + + /** + * Return the class ID for this class. This is useful only for + * comparing to a return value from getDynamicClassID(). For example: + * <pre> + * . Base* polymorphic_pointer = createPolymorphicObject(); + * . if (polymorphic_pointer->getDynamicClassID() == + * . Derived::getStaticClassID()) ... + * </pre> + * @return The class ID for all objects of this class. + * @stable ICU 2.0 + */ + static UClassID U_EXPORT2 getStaticClassID(void); + +#ifndef U_HIDE_INTERNAL_API + /** + * Compares two Format objects. This is used for constructing the hash + * tables. + * + * @param left pointer to a Format object. Must not be nullptr. + * @param right pointer to a Format object. Must not be nullptr. + * + * @return whether the two objects are the same + * @internal + */ + static UBool equalFormats(const void* left, const void* right); +#endif /* U_HIDE_INTERNAL_API */ + +private: + + Locale fLocale; + MessagePattern msgPattern; + Format** formatAliases; // see getFormats + int32_t formatAliasesCapacity; + + MessageFormat() = delete; // default constructor not implemented + + /** + * This provider helps defer instantiation of a PluralRules object + * until we actually need to select a keyword. + * For example, if the number matches an explicit-value selector like "=1" + * we do not need any PluralRules. + */ + class U_I18N_API PluralSelectorProvider : public PluralFormat::PluralSelector { + public: + PluralSelectorProvider(const MessageFormat &mf, UPluralType type); + virtual ~PluralSelectorProvider(); + virtual UnicodeString select(void *ctx, double number, UErrorCode& ec) const override; + + void reset(); + private: + const MessageFormat &msgFormat; + PluralRules* rules; + UPluralType type; + }; + + /** + * A MessageFormat formats an array of arguments. Each argument + * has an expected type, based on the pattern. For example, if + * the pattern contains the subformat "{3,number,integer}", then + * we expect argument 3 to have type Formattable::kLong. This + * array needs to grow dynamically if the MessageFormat is + * modified. + */ + Formattable::Type* argTypes; + int32_t argTypeCount; + int32_t argTypeCapacity; + + /** + * true if there are different argTypes for the same argument. + * This only matters when the MessageFormat is used in the plain C (umsg_xxx) API + * where the pattern argTypes determine how the va_arg list is read. + */ + UBool hasArgTypeConflicts; + + // Variable-size array management + UBool allocateArgTypes(int32_t capacity, UErrorCode& status); + + /** + * Default Format objects used when no format is specified and a + * numeric or date argument is formatted. These are volatile + * cache objects maintained only for performance. They do not + * participate in operator=(), copy constructor(), nor + * operator==(). + */ + NumberFormat* defaultNumberFormat; + DateFormat* defaultDateFormat; + + UHashtable* cachedFormatters; + UHashtable* customFormatArgStarts; + + PluralSelectorProvider pluralProvider; + PluralSelectorProvider ordinalProvider; + + /** + * Method to retrieve default formats (or nullptr on failure). + * These are semantically const, but may modify *this. + */ + const NumberFormat* getDefaultNumberFormat(UErrorCode&) const; + const DateFormat* getDefaultDateFormat(UErrorCode&) const; + + /** + * Finds the word s, in the keyword list and returns the located index. + * @param s the keyword to be searched for. + * @param list the list of keywords to be searched with. + * @return the index of the list which matches the keyword s. + */ + static int32_t findKeyword( const UnicodeString& s, + const char16_t * const *list); + + /** + * Thin wrapper around the format(... AppendableWrapper ...) variant. + * Wraps the destination UnicodeString into an AppendableWrapper and + * supplies default values for some other parameters. + */ + UnicodeString& format(const Formattable* arguments, + const UnicodeString *argumentNames, + int32_t cnt, + UnicodeString& appendTo, + FieldPosition* pos, + UErrorCode& status) const; + + /** + * Formats the arguments and writes the result into the + * AppendableWrapper, updates the field position. + * + * @param msgStart Index to msgPattern part to start formatting from. + * @param plNumber nullptr except when formatting a plural argument sub-message + * where a '#' is replaced by the format string for this number. + * @param arguments The formattable objects array. (Must not be nullptr.) + * @param argumentNames nullptr if numbered values are used. Otherwise the same + * length as "arguments", and each entry is the name of the + * corresponding argument in "arguments". + * @param cnt The length of arguments (and of argumentNames if that is not nullptr). + * @param appendTo Output parameter to receive the result. + * The result string is appended to existing contents. + * @param pos Field position status. + * @param success The error code status. + */ + void format(int32_t msgStart, + const void *plNumber, + const Formattable* arguments, + const UnicodeString *argumentNames, + int32_t cnt, + AppendableWrapper& appendTo, + FieldPosition* pos, + UErrorCode& success) const; + + UnicodeString getArgName(int32_t partIndex); + + void setArgStartFormat(int32_t argStart, Format* formatter, UErrorCode& status); + + void setCustomArgStartFormat(int32_t argStart, Format* formatter, UErrorCode& status); + + int32_t nextTopLevelArgStart(int32_t partIndex) const; + + UBool argNameMatches(int32_t partIndex, const UnicodeString& argName, int32_t argNumber); + + void cacheExplicitFormats(UErrorCode& status); + + Format* createAppropriateFormat(UnicodeString& type, + UnicodeString& style, + Formattable::Type& formattableType, + UParseError& parseError, + UErrorCode& ec); + + const Formattable* getArgFromListByName(const Formattable* arguments, + const UnicodeString *argumentNames, + int32_t cnt, UnicodeString& name) const; + + Formattable* parse(int32_t msgStart, + const UnicodeString& source, + ParsePosition& pos, + int32_t& count, + UErrorCode& ec) const; + + FieldPosition* updateMetaData(AppendableWrapper& dest, int32_t prevLength, + FieldPosition* fp, const Formattable* argId) const; + + /** + * Finds the "other" sub-message. + * @param partIndex the index of the first PluralFormat argument style part. + * @return the "other" sub-message start part index. + */ + int32_t findOtherSubMessage(int32_t partIndex) const; + + /** + * Returns the ARG_START index of the first occurrence of the plural number in a sub-message. + * Returns -1 if it is a REPLACE_NUMBER. + * Returns 0 if there is neither. + */ + int32_t findFirstPluralNumberArg(int32_t msgStart, const UnicodeString &argName) const; + + Format* getCachedFormatter(int32_t argumentNumber) const; + + UnicodeString getLiteralStringUntilNextArgument(int32_t from) const; + + void copyObjects(const MessageFormat& that, UErrorCode& ec); + + void formatComplexSubMessage(int32_t msgStart, + const void *plNumber, + const Formattable* arguments, + const UnicodeString *argumentNames, + int32_t cnt, + AppendableWrapper& appendTo, + UErrorCode& success) const; + + /** + * Convenience method that ought to be in NumberFormat + */ + NumberFormat* createIntegerFormat(const Locale& locale, UErrorCode& status) const; + + /** + * Returns array of argument types in the parsed pattern + * for use in C API. Only for the use of umsg_vformat(). Not + * for public consumption. + * @param listCount Output parameter to receive the size of array + * @return The array of formattable types in the pattern + */ + const Formattable::Type* getArgTypeList(int32_t& listCount) const { + listCount = argTypeCount; + return argTypes; + } + + /** + * Resets the internal MessagePattern, and other associated caches. + */ + void resetPattern(); + + /** + * A DummyFormatter that we use solely to store a nullptr value. UHash does + * not support storing nullptr values. + */ + class U_I18N_API DummyFormat : public Format { + public: + virtual bool operator==(const Format&) const override; + virtual DummyFormat* clone() const override; + virtual UnicodeString& format(const Formattable& obj, + UnicodeString& appendTo, + UErrorCode& status) const; + virtual UnicodeString& format(const Formattable&, + UnicodeString& appendTo, + FieldPosition&, + UErrorCode& status) const override; + virtual UnicodeString& format(const Formattable& obj, + UnicodeString& appendTo, + FieldPositionIterator* posIter, + UErrorCode& status) const override; + virtual void parseObject(const UnicodeString&, + Formattable&, + ParsePosition&) const override; + }; + + friend class MessageFormatAdapter; // getFormatTypeList() access +}; + +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_FORMATTING */ + +#endif /* U_SHOW_CPLUSPLUS_API */ + +#endif // _MSGFMT +//eof |