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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
********************************************************************************
* Copyright (C) 1997-2013, International Business Machines
* Corporation and others. All Rights Reserved.
********************************************************************************
*
* File CHOICFMT.H
*
* Modification History:
*
* Date Name Description
* 02/19/97 aliu Converted from java.
* 03/20/97 helena Finished first cut of implementation and got rid
* of nextDouble/previousDouble and replaced with
* boolean array.
* 4/10/97 aliu Clean up. Modified to work on AIX.
* 8/6/97 nos Removed overloaded constructor, member var 'buffer'.
* 07/22/98 stephen Removed operator!= (implemented in Format)
********************************************************************************
*/
#ifndef CHOICFMT_H
#define CHOICFMT_H
#include "unicode/utypes.h"
#if U_SHOW_CPLUSPLUS_API
/**
* \file
* \brief C++ API: Choice Format.
*/
#if !UCONFIG_NO_FORMATTING
#include "unicode/fieldpos.h"
#include "unicode/format.h"
#include "unicode/messagepattern.h"
#include "unicode/numfmt.h"
#include "unicode/unistr.h"
#ifndef U_HIDE_DEPRECATED_API
U_NAMESPACE_BEGIN
class MessageFormat;
/**
* ChoiceFormat converts between ranges of numeric values and strings for those ranges.
* The strings must conform to the MessageFormat pattern syntax.
*
* <p><em><code>ChoiceFormat</code> is probably not what you need.
* Please use <code>MessageFormat</code>
* with <code>plural</code> arguments for proper plural selection,
* and <code>select</code> arguments for simple selection among a fixed set of choices!</em></p>
*
* <p>A <code>ChoiceFormat</code> splits
* the real number line \htmlonly<code>-&#x221E;</code> to
* <code>+&#x221E;</code>\endhtmlonly into two
* or more contiguous ranges. Each range is mapped to a
* string.</p>
*
* <p><code>ChoiceFormat</code> was originally intended
* for displaying grammatically correct
* plurals such as &quot;There is one file.&quot; vs. &quot;There are 2 files.&quot;
* <em>However,</em> plural rules for many languages
* are too complex for the capabilities of ChoiceFormat,
* and its requirement of specifying the precise rules for each message
* is unmanageable for translators.</p>
*
* <p>There are two methods of defining a <code>ChoiceFormat</code>; both
* are equivalent. The first is by using a string pattern. This is the
* preferred method in most cases. The second method is through direct
* specification of the arrays that logically make up the
* <code>ChoiceFormat</code>.</p>
*
* <p>Note: Typically, choice formatting is done (if done at all) via <code>MessageFormat</code>
* with a <code>choice</code> argument type,
* rather than using a stand-alone <code>ChoiceFormat</code>.</p>
*
* <h5>Patterns and Their Interpretation</h5>
*
* <p>The pattern string defines the range boundaries and the strings for each number range.
* Syntax:
* <pre>
* choiceStyle = number separator message ('|' number separator message)*
* number = normal_number | ['-'] \htmlonly&#x221E;\endhtmlonly (U+221E, infinity)
* normal_number = double value (unlocalized ASCII string)
* separator = less_than | less_than_or_equal
* less_than = '<'
* less_than_or_equal = '#' | \htmlonly&#x2264;\endhtmlonly (U+2264)
* message: see {@link MessageFormat}
* </pre>
* Pattern_White_Space between syntax elements is ignored, except
* around each range's sub-message.</p>
*
* <p>Each numeric sub-range extends from the current range's number
* to the next range's number.
* The number itself is included in its range if a <code>less_than_or_equal</code> sign is used,
* and excluded from its range (and instead included in the previous range)
* if a <code>less_than</code> sign is used.</p>
*
* <p>When a <code>ChoiceFormat</code> is constructed from
* arrays of numbers, closure flags and strings,
* they are interpreted just like
* the sequence of <code>(number separator string)</code> in an equivalent pattern string.
* <code>closure[i]==true</code> corresponds to a <code>less_than</code> separator sign.
* The equivalent pattern string will be constructed automatically.</p>
*
* <p>During formatting, a number is mapped to the first range
* where the number is not greater than the range's upper limit.
* That range's message string is returned. A NaN maps to the very first range.</p>
*
* <p>During parsing, a range is selected for the longest match of
* any range's message. That range's number is returned, ignoring the separator/closure.
* Only a simple string match is performed, without parsing of arguments that
* might be specified in the message strings.</p>
*
* <p>Note that the first range's number is ignored in formatting
* but may be returned from parsing.</p>
*
* <h5>Examples</h5>
*
* <p>Here is an example of two arrays that map the number
* <code>1..7</code> to the English day of the week abbreviations
* <code>Sun..Sat</code>. No closures array is given; this is the same as
* specifying all closures to be <code>false</code>.</p>
*
* <pre> {1,2,3,4,5,6,7},
* {&quot;Sun&quot;,&quot;Mon&quot;,&quot;Tue&quot;,&quot;Wed&quot;,&quot;Thur&quot;,&quot;Fri&quot;,&quot;Sat&quot;}</pre>
*
* <p>Here is an example that maps the ranges [-Inf, 1), [1, 1], and (1,
* +Inf] to three strings. That is, the number line is split into three
* ranges: x &lt; 1.0, x = 1.0, and x &gt; 1.0.
* (The round parentheses in the notation above indicate an exclusive boundary,
* like the turned bracket in European notation: [-Inf, 1) == [-Inf, 1[ )</p>
*
* <pre> {0, 1, 1},
* {false, false, true},
* {&quot;no files&quot;, &quot;one file&quot;, &quot;many files&quot;}</pre>
*
* <p>Here is an example that shows formatting and parsing: </p>
*
* \code
* #include <unicode/choicfmt.h>
* #include <unicode/unistr.h>
* #include <iostream.h>
*
* int main(int argc, char *argv[]) {
* double limits[] = {1,2,3,4,5,6,7};
* UnicodeString monthNames[] = {
* "Sun","Mon","Tue","Wed","Thu","Fri","Sat"};
* ChoiceFormat fmt(limits, monthNames, 7);
* UnicodeString str;
* char buf[256];
* for (double x = 1.0; x <= 8.0; x += 1.0) {
* fmt.format(x, str);
* str.extract(0, str.length(), buf, 256, "");
* str.truncate(0);
* cout << x << " -> "
* << buf << endl;
* }
* cout << endl;
* return 0;
* }
* \endcode
*
* <p><em>User subclasses are not supported.</em> While clients may write
* subclasses, such code will not necessarily work and will not be
* guaranteed to work stably from release to release.
*
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
class U_I18N_API ChoiceFormat: public NumberFormat {
public:
/**
* Constructs a new ChoiceFormat from the pattern string.
*
* @param pattern Pattern used to construct object.
* @param status Output param to receive success code. If the
* pattern cannot be parsed, set to failure code.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
ChoiceFormat(const UnicodeString& pattern,
UErrorCode& status);
/**
* Constructs a new ChoiceFormat with the given limits and message strings.
* All closure flags default to <code>false</code>,
* equivalent to <code>less_than_or_equal</code> separators.
*
* Copies the limits and formats instead of adopting them.
*
* @param limits Array of limit values.
* @param formats Array of formats.
* @param count Size of 'limits' and 'formats' arrays.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
ChoiceFormat(const double* limits,
const UnicodeString* formats,
int32_t count );
/**
* Constructs a new ChoiceFormat with the given limits, closure flags and message strings.
*
* Copies the limits and formats instead of adopting them.
*
* @param limits Array of limit values
* @param closures Array of booleans specifying whether each
* element of 'limits' is open or closed. If false, then the
* corresponding limit number is a member of its range.
* If true, then the limit number belongs to the previous range it.
* @param formats Array of formats
* @param count Size of 'limits', 'closures', and 'formats' arrays
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
ChoiceFormat(const double* limits,
const UBool* closures,
const UnicodeString* formats,
int32_t count);
/**
* Copy constructor.
*
* @param that ChoiceFormat object to be copied from
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
ChoiceFormat(const ChoiceFormat& that);
/**
* Assignment operator.
*
* @param that ChoiceFormat object to be copied
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
const ChoiceFormat& operator=(const ChoiceFormat& that);
/**
* Destructor.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual ~ChoiceFormat();
/**
* Clones this Format object. The caller owns the
* result and must delete it when done.
*
* @return a copy of this object
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual ChoiceFormat* clone() const;
/**
* Returns true if the given Format objects are semantically equal.
* Objects of different subclasses are considered unequal.
*
* @param other ChoiceFormat object to be compared
* @return true if other is the same as this.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UBool operator==(const Format& other) const;
/**
* Sets the pattern.
* @param pattern The pattern to be applied.
* @param status Output param set to success/failure code on
* exit. If the pattern is invalid, this will be
* set to a failure result.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual void applyPattern(const UnicodeString& pattern,
UErrorCode& status);
/**
* Sets the pattern.
* @param pattern The pattern to be applied.
* @param parseError Struct to receive information on position
* of error if an error is encountered
* @param status Output param set to success/failure code on
* exit. If the pattern is invalid, this will be
* set to a failure result.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual void applyPattern(const UnicodeString& pattern,
UParseError& parseError,
UErrorCode& status);
/**
* Gets the pattern.
*
* @param pattern Output param which will receive the pattern
* Previous contents are deleted.
* @return A reference to 'pattern'
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UnicodeString& toPattern(UnicodeString &pattern) const;
/**
* Sets the choices to be used in formatting.
* For details see the constructor with the same parameter list.
*
* @param limitsToCopy Contains the top value that you want
* parsed with that format,and should be in
* ascending sorted order. When formatting X,
* the choice will be the i, where limit[i]
* &lt;= X &lt; limit[i+1].
* @param formatsToCopy The format strings you want to use for each limit.
* @param count The size of the above arrays.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual void setChoices(const double* limitsToCopy,
const UnicodeString* formatsToCopy,
int32_t count );
/**
* Sets the choices to be used in formatting.
* For details see the constructor with the same parameter list.
*
* @param limits Array of limits
* @param closures Array of limit booleans
* @param formats Array of format string
* @param count The size of the above arrays
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual void setChoices(const double* limits,
const UBool* closures,
const UnicodeString* formats,
int32_t count);
/**
* Returns NULL and 0.
* Before ICU 4.8, this used to return the choice limits array.
*
* @param count Will be set to 0.
* @return NULL
* @deprecated ICU 4.8 Use the MessagePattern class to analyze a ChoiceFormat pattern.
*/
virtual const double* getLimits(int32_t& count) const;
/**
* Returns NULL and 0.
* Before ICU 4.8, this used to return the limit booleans array.
*
* @param count Will be set to 0.
* @return NULL
* @deprecated ICU 4.8 Use the MessagePattern class to analyze a ChoiceFormat pattern.
*/
virtual const UBool* getClosures(int32_t& count) const;
/**
* Returns NULL and 0.
* Before ICU 4.8, this used to return the array of choice strings.
*
* @param count Will be set to 0.
* @return NULL
* @deprecated ICU 4.8 Use the MessagePattern class to analyze a ChoiceFormat pattern.
*/
virtual const UnicodeString* getFormats(int32_t& count) const;
using NumberFormat::format;
/**
* Formats a double number using this object's choices.
*
* @param number The value 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.
* @return Reference to 'appendTo' parameter.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UnicodeString& format(double number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Formats an int32_t number using this object's choices.
*
* @param number The value 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.
* @return Reference to 'appendTo' parameter.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UnicodeString& format(int32_t number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Formats an int64_t number using this object's choices.
*
* @param number The value 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.
* @return Reference to 'appendTo' parameter.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UnicodeString& format(int64_t number,
UnicodeString& appendTo,
FieldPosition& pos) const;
/**
* Formats an array of objects using this object's choices.
*
* @param objs The array of objects to be formatted.
* @param cnt The size of objs.
* @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 success Output param set to success/failure code on
* exit.
* @return Reference to 'appendTo' parameter.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UnicodeString& format(const Formattable* objs,
int32_t cnt,
UnicodeString& appendTo,
FieldPosition& pos,
UErrorCode& success) const;
using NumberFormat::parse;
/**
* Looks for the longest match of any message string on the input text and,
* if there is a match, sets the result object to the corresponding range's number.
*
* If no string matches, then the parsePosition is unchanged.
*
* @param text The text to be parsed.
* @param result Formattable to be set to the parse result.
* If parse fails, return contents are undefined.
* @param parsePosition The position to start parsing at on input.
* On output, moved to after the last successfully
* parse character. On parse failure, does not change.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual void parse(const UnicodeString& text,
Formattable& result,
ParsePosition& parsePosition) const;
/**
* Returns a unique class ID POLYMORPHICALLY. Part of ICU's "poor man's RTTI".
*
* @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.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
virtual UClassID getDynamicClassID(void) const;
/**
* Returns 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.
* @deprecated ICU 49 Use MessageFormat instead, with plural and select arguments.
*/
static UClassID U_EXPORT2 getStaticClassID(void);
private:
/**
* Converts a double value to a string.
* @param value the double number to be converted.
* @param string the result string.
* @return the converted string.
*/
static UnicodeString& dtos(double value, UnicodeString& string);
ChoiceFormat(); // default constructor not implemented
/**
* Construct a new ChoiceFormat with the limits and the corresponding formats
* based on the pattern.
*
* @param newPattern Pattern used to construct object.
* @param parseError Struct to receive information on position
* of error if an error is encountered.
* @param status Output param to receive success code. If the
* pattern cannot be parsed, set to failure code.
*/
ChoiceFormat(const UnicodeString& newPattern,
UParseError& parseError,
UErrorCode& status);
friend class MessageFormat;
virtual void setChoices(const double* limits,
const UBool* closures,
const UnicodeString* formats,
int32_t count,
UErrorCode &errorCode);
/**
* Finds the ChoiceFormat sub-message for the given number.
* @param pattern A MessagePattern.
* @param partIndex the index of the first ChoiceFormat argument style part.
* @param number a number to be mapped to one of the ChoiceFormat argument's intervals
* @return the sub-message start part index.
*/
static int32_t findSubMessage(const MessagePattern &pattern, int32_t partIndex, double number);
static double parseArgument(
const MessagePattern &pattern, int32_t partIndex,
const UnicodeString &source, ParsePosition &pos);
/**
* Matches the pattern string from the end of the partIndex to
* the beginning of the limitPartIndex,
* including all syntax except SKIP_SYNTAX,
* against the source string starting at sourceOffset.
* If they match, returns the length of the source string match.
* Otherwise returns -1.
*/
static int32_t matchStringUntilLimitPart(
const MessagePattern &pattern, int32_t partIndex, int32_t limitPartIndex,
const UnicodeString &source, int32_t sourceOffset);
/**
* Some of the ChoiceFormat constructors do not have a UErrorCode paramater.
* We need _some_ way to provide one for the MessagePattern constructor.
* Alternatively, the MessagePattern could be a pointer field, but that is
* not nice either.
*/
UErrorCode constructorErrorCode;
/**
* The MessagePattern which contains the parsed structure of the pattern string.
*
* Starting with ICU 4.8, the MessagePattern contains a sequence of
* numeric/selector/message parts corresponding to the parsed pattern.
* For details see the MessagePattern class API docs.
*/
MessagePattern msgPattern;
/**
* Docs & fields from before ICU 4.8, before MessagePattern was used.
* Commented out, and left only for explanation of semantics.
* --------
* Each ChoiceFormat divides the range -Inf..+Inf into fCount
* intervals. The intervals are:
*
* 0: fChoiceLimits[0]..fChoiceLimits[1]
* 1: fChoiceLimits[1]..fChoiceLimits[2]
* ...
* fCount-2: fChoiceLimits[fCount-2]..fChoiceLimits[fCount-1]
* fCount-1: fChoiceLimits[fCount-1]..+Inf
*
* Interval 0 is special; during formatting (mapping numbers to
* strings), it also contains all numbers less than
* fChoiceLimits[0], as well as NaN values.
*
* Interval i maps to and from string fChoiceFormats[i]. When
* parsing (mapping strings to numbers), then intervals map to
* their lower limit, that is, interval i maps to fChoiceLimit[i].
*
* The intervals may be closed, half open, or open. This affects
* formatting but does not affect parsing. Interval i is affected
* by fClosures[i] and fClosures[i+1]. If fClosures[i]
* is false, then the value fChoiceLimits[i] is in interval i.
* That is, intervals i and i are:
*
* i-1: ... x < fChoiceLimits[i]
* i: fChoiceLimits[i] <= x ...
*
* If fClosures[i] is true, then the value fChoiceLimits[i] is
* in interval i-1. That is, intervals i-1 and i are:
*
* i-1: ... x <= fChoiceLimits[i]
* i: fChoiceLimits[i] < x ...
*
* Because of the nature of interval 0, fClosures[0] has no
* effect.
*/
// double* fChoiceLimits;
// UBool* fClosures;
// UnicodeString* fChoiceFormats;
// int32_t fCount;
};
U_NAMESPACE_END
#endif // U_HIDE_DEPRECATED_API
#endif /* #if !UCONFIG_NO_FORMATTING */
#endif /* U_SHOW_CPLUSPLUS_API */
#endif // CHOICFMT_H
//eof