/******************************************************************** * COPYRIGHT: * Copyright (c) 1997-2011, International Business Machines Corporation and * others. All Rights Reserved. * Copyright (C) 2010 , Yahoo! Inc. ******************************************************************** * * File SELFMT.H * * Modification History: * * Date Name Description * 11/11/09 kirtig Finished first cut of implementation. ********************************************************************/ #ifndef SELFMT #define SELFMT #include "unicode/messagepattern.h" #include "unicode/numfmt.h" #include "unicode/utypes.h" /** * \file * \brief C++ API: SelectFormat object */ #if !UCONFIG_NO_FORMATTING U_NAMESPACE_BEGIN class MessageFormat; /** * <p><code>SelectFormat</code> supports the creation of internationalized * messages by selecting phrases based on keywords. The pattern specifies * how to map keywords to phrases and provides a default phrase. The * object provided to the format method is a string that's matched * against the keywords. If there is a match, the corresponding phrase * is selected; otherwise, the default phrase is used.</p> * * <h4>Using <code>SelectFormat</code> for Gender Agreement</h4> * * <p>Note: Typically, select formatting is done via <code>MessageFormat</code> * with a <code>select</code> argument type, * rather than using a stand-alone <code>SelectFormat</code>.</p> * * <p>The main use case for the select format is gender based inflection. * When names or nouns are inserted into sentences, their gender can affect pronouns, * verb forms, articles, and adjectives. Special care needs to be * taken for the case where the gender cannot be determined. * The impact varies between languages:</p> * \htmlonly * <ul> * <li>English has three genders, and unknown gender is handled as a special * case. Names use the gender of the named person (if known), nouns referring * to people use natural gender, and inanimate objects are usually neutral. * The gender only affects pronouns: "he", "she", "it", "they". * * <li>German differs from English in that the gender of nouns is rather * arbitrary, even for nouns referring to people ("Mädchen", girl, is neutral). * The gender affects pronouns ("er", "sie", "es"), articles ("der", "die", * "das"), and adjective forms ("guter Mann", "gute Frau", "gutes Mädchen"). * * <li>French has only two genders; as in German the gender of nouns * is rather arbitrary - for sun and moon, the genders * are the opposite of those in German. The gender affects * pronouns ("il", "elle"), articles ("le", "la"), * adjective forms ("bon", "bonne"), and sometimes * verb forms ("allé", "allée"). * * <li>Polish distinguishes five genders (or noun classes), * human masculine, animate non-human masculine, inanimate masculine, * feminine, and neuter. * </ul> * \endhtmlonly * <p>Some other languages have noun classes that are not related to gender, * but similar in grammatical use. * Some African languages have around 20 noun classes.</p> * * <p><b>Note:</b>For the gender of a <i>person</i> in a given sentence, * we usually need to distinguish only between female, male and other/unknown.</p> * * <p>To enable localizers to create sentence patterns that take their * language's gender dependencies into consideration, software has to provide * information about the gender associated with a noun or name to * <code>MessageFormat</code>. * Two main cases can be distinguished:</p> * * <ul> * <li>For people, natural gender information should be maintained for each person. * Keywords like "male", "female", "mixed" (for groups of people) * and "unknown" could be used. * * <li>For nouns, grammatical gender information should be maintained for * each noun and per language, e.g., in resource bundles. * The keywords "masculine", "feminine", and "neuter" are commonly used, * but some languages may require other keywords. * </ul> * * <p>The resulting keyword is provided to <code>MessageFormat</code> as a * parameter separate from the name or noun it's associated with. For example, * to generate a message such as "Jean went to Paris", three separate arguments * would be provided: The name of the person as argument 0, the gender of * the person as argument 1, and the name of the city as argument 2. * The sentence pattern for English, where the gender of the person has * no impact on this simple sentence, would not refer to argument 1 at all:</p> * * <pre>{0} went to {2}.</pre> * * <p><b>Note:</b> The entire sentence should be included (and partially repeated) * inside each phrase. Otherwise translators would have to be trained on how to * move bits of the sentence in and out of the select argument of a message. * (The examples below do not follow this recommendation!)</p> * * <p>The sentence pattern for French, where the gender of the person affects * the form of the participle, uses a select format based on argument 1:</p> * * \htmlonly<pre>{0} est {1, select, female {allée} other {allé}} à {2}.</pre>\endhtmlonly * * <p>Patterns can be nested, so that it's possible to handle interactions of * number and gender where necessary. For example, if the above sentence should * allow for the names of several people to be inserted, the following sentence * pattern can be used (with argument 0 the list of people's names, * argument 1 the number of people, argument 2 their combined gender, and * argument 3 the city name):</p> * * \htmlonly * <pre>{0} {1, plural, * one {est {2, select, female {allée} other {allé}}} * other {sont {2, select, female {allées} other {allés}}} * }à {3}.</pre> * \endhtmlonly * * <h4>Patterns and Their Interpretation</h4> * * <p>The <code>SelectFormat</code> pattern string defines the phrase output * for each user-defined keyword. * The pattern is a sequence of (keyword, message) pairs. * A keyword is a "pattern identifier": [^[[:Pattern_Syntax:][:Pattern_White_Space:]]]+</p> * * <p>Each message is a MessageFormat pattern string enclosed in {curly braces}.</p> * * <p>You always have to define a phrase for the default keyword * <code>other</code>; this phrase is returned when the keyword * provided to * the <code>format</code> method matches no other keyword. * If a pattern does not provide a phrase for <code>other</code>, the method * it's provided to returns the error <code>U_DEFAULT_KEYWORD_MISSING</code>. * <br> * Pattern_White_Space between keywords and messages is ignored. * Pattern_White_Space within a message is preserved and output.</p> * * <p><pre>Example: * \htmlonly * * UErrorCode status = U_ZERO_ERROR; * MessageFormat *msgFmt = new MessageFormat(UnicodeString("{0} est {1, select, female {allée} other {allé}} à Paris."), Locale("fr"), status); * if (U_FAILURE(status)) { * return; * } * FieldPosition ignore(FieldPosition::DONT_CARE); * UnicodeString result; * * char* str1= "Kirti,female"; * Formattable args1[] = {"Kirti","female"}; * msgFmt->format(args1, 2, result, ignore, status); * cout << "Input is " << str1 << " and result is: " << result << endl; * delete msgFmt; * * \endhtmlonly * </pre> * </p> * * Produces the output:<br> * \htmlonly * <code>Kirti est allée à Paris.</code> * \endhtmlonly * * @stable ICU 4.4 */ class U_I18N_API SelectFormat : public Format { public: /** * Creates a new <code>SelectFormat</code> for a given pattern string. * @param pattern the pattern for this <code>SelectFormat</code>. * errors are returned to status if the pattern is invalid. * @param status output param set to success/failure code on exit, which * must not indicate a failure before the function call. * @stable ICU 4.4 */ SelectFormat(const UnicodeString& pattern, UErrorCode& status); /** * copy constructor. * @stable ICU 4.4 */ SelectFormat(const SelectFormat& other); /** * Destructor. * @stable ICU 4.4 */ virtual ~SelectFormat(); /** * Sets the pattern used by this select format. * for the keyword rules. * Patterns and their interpretation are specified in the class description. * * @param pattern the pattern for this select format * errors are returned to status if the pattern is invalid. * @param status output param set to success/failure code on exit, which * must not indicate a failure before the function call. * @stable ICU 4.4 */ void applyPattern(const UnicodeString& pattern, UErrorCode& status); using Format::format; /** * Selects the phrase for the given keyword * * @param keyword The keyword that is used to select an alternative. * @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 output param set to success/failure code on exit, which * must not indicate a failure before the function call. * @return Reference to 'appendTo' parameter. * @stable ICU 4.4 */ UnicodeString& format(const UnicodeString& keyword, UnicodeString& appendTo, FieldPosition& pos, UErrorCode& status) const; /** * Assignment operator * * @param other the SelectFormat object to copy from. * @stable ICU 4.4 */ SelectFormat& operator=(const SelectFormat& other); /** * Return true if another object is semantically equal to this one. * * @param other the SelectFormat object to be compared with. * @return true if other is semantically equal to this. * @stable ICU 4.4 */ virtual UBool operator==(const Format& other) const; /** * Return true if another object is semantically unequal to this one. * * @param other the SelectFormat object to be compared with. * @return true if other is semantically unequal to this. * @stable ICU 4.4 */ virtual UBool operator!=(const Format& other) const; /** * Clones this Format object polymorphically. The caller owns the * result and should delete it when done. * @stable ICU 4.4 */ virtual Format* clone(void) const; /** * Format an object to produce a string. * This method handles keyword strings. * If the Formattable object is not a <code>UnicodeString</code>, * then it returns a failing UErrorCode. * * @param obj A keyword string that is used to select an alternative. * @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 output param filled with success/failure status. * @return Reference to 'appendTo' parameter. * @stable ICU 4.4 */ UnicodeString& format(const Formattable& obj, UnicodeString& appendTo, FieldPosition& pos, UErrorCode& status) const; /** * Returns the pattern from applyPattern() or constructor. * * @param appendTo output parameter to receive result. * Result is appended to existing contents. * @return the UnicodeString with inserted pattern. * @stable ICU 4.4 */ UnicodeString& toPattern(UnicodeString& appendTo); /** * This method is not yet supported by <code>SelectFormat</code>. * <P> * Before calling, set parse_pos.index to the offset you want to start * parsing at in the source. After calling, parse_pos.index is the end of * the text you parsed. If error occurs, index is unchanged. * <P> * When parsing, leading whitespace is discarded (with a successful parse), * while trailing whitespace is left as is. * <P> * See Format::parseObject() for more. * * @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 parse_pos The position to start parsing at. Upon return * this param is set to the position after the * last character successfully parsed. If the * source is not parsed successfully, this param * will remain unchanged. * @stable ICU 4.4 */ virtual void parseObject(const UnicodeString& source, Formattable& result, ParsePosition& parse_pos) const; /** * ICU "poor man's RTTI", returns a UClassID for this class. * @stable ICU 4.4 */ static UClassID U_EXPORT2 getStaticClassID(void); /** * ICU "poor man's RTTI", returns a UClassID for the actual class. * @stable ICU 4.4 */ virtual UClassID getDynamicClassID() const; private: friend class MessageFormat; SelectFormat(); // default constructor not implemented. /** * Finds the SelectFormat sub-message for the given keyword, or the "other" sub-message. * @param pattern A MessagePattern. * @param partIndex the index of the first SelectFormat argument style part. * @param keyword a keyword to be matched to one of the SelectFormat argument's keywords. * @param ec Error code. * @return the sub-message start part index. */ static int32_t findSubMessage(const MessagePattern& pattern, int32_t partIndex, const UnicodeString& keyword, UErrorCode& ec); MessagePattern msgPattern; }; U_NAMESPACE_END #endif /* #if !UCONFIG_NO_FORMATTING */ #endif // _SELFMT //eof