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* Copyright (C) 1996-1999, International Business Machines
* Corporation and others. All Rights Reserved.
#ifndef COMPITR_H
#define COMPITR_H
#include "unicode/utypes.h"
#include "unicode/unistr.h"
* <tt>ComposedCharIter</tt> is an iterator class that returns all
* of the precomposed characters defined in the Unicode standard, along
* with their decomposed forms. This is often useful when building
* data tables (<i>e.g.</i> collation tables) which need to treat composed
* and decomposed characters equivalently.
* <p>
* For example, imagine that you have built a collation table with ordering
* rules for the {@link Normalizer#DECOMP canonically decomposed} forms of all
* characters used in a particular language. When you process input text using
* this table, the text must first be decomposed so that it matches the form
* used in the table. This can impose a performance penalty that may be
* unacceptable in some situations.
* <p>
* You can avoid this problem by ensuring that the collation table contains
* rules for both the decomposed <i>and</i> composed versions of each character.
* To do so, use a <tt>ComposedCharIter</tt> to iterate through all of the
* composed characters in Unicode. If the decomposition for that character
* consists solely of characters that are listed in your ruleset, you can
* add a new rule for the composed character that makes it equivalent to
* its decomposition sequence.
* <p>
* Note that <tt>ComposedCharIter</tt> iterates over a <em>static</em> table
* of the composed characters in Unicode. If you want to iterate over the
* composed characters in a particular string, use {@link Normalizer} instead.
* <p>
* When constructing a <tt>ComposedCharIter</tt> there is one
* optional feature that you can enable or disable:
* <ul>
* <li>{@link Normalizer#IGNORE_HANGUL} - Do not iterate over the Hangul
* characters and their corresponding Jamo decompositions.
* This option is off by default (<i>i.e.</i> Hangul processing is enabled)
* since the Unicode standard specifies that Hangul to Jamo
* is a canonical decomposition.
* </ul>
* <p>
* <tt>ComposedCharIter</tt> is currently based on version 2.1.8 of the
* <a href="" target="unicode">Unicode Standard</a>.
* It will be updated as later versions of Unicode are released.
class U_COMMON_API ComposedCharIter
* Constant that indicates the iteration has completed.
* {@link #next} returns this value when there are no more composed
* characters over which to iterate.
static const UChar DONE;
* Construct a new <tt>ComposedCharIter</tt>. The iterator will return
* all Unicode characters with canonical decompositions, including Korean
* Hangul characters.
* Constructs a non-default <tt>ComposedCharIter</tt> with optional behavior.
* <p>
* @param compat <tt>false</tt> for canonical decompositions only;
* <tt>true</tt> for both canonical and compatibility
* decompositions.
* @param options Optional decomposition features. Currently, the only
* supported option is {@link Normalizer#IGNORE_HANGUL}, which
* causes this <tt>ComposedCharIter</tt> not to iterate
* over the Hangul characters and their corresponding
* Jamo decompositions.
ComposedCharIter(bool_t compat, int32_t options);
* Determines whether there any precomposed Unicode characters not yet returned
* by {@link #next}.
bool_t hasNext(void) const;
* Returns the next precomposed Unicode character.
* Repeated calls to <tt>next</tt> return all of the precomposed characters defined
* by Unicode, in ascending order. After all precomposed characters have
* been returned, {@link #hasNext} will return <tt>false</tt> and further calls
* to <tt>next</tt> will return {@link #DONE}.
UChar next(void);
* Returns the Unicode decomposition of the current character.
* This method returns the decomposition of the precomposed character most
* recently returned by {@link #next}. The resulting decomposition is
* affected by the settings of the options passed to the constructor.
* and {@link Normalizer#NO_HANGUL NO_HANGUL} options passed to the constructor.
void getDecomposition(UnicodeString& result) const;
void findNextChar(void);
int32_t minDecomp;
bool_t hangul;
UChar curChar;
UChar nextChar;
#endif // _COMPITR