summaryrefslogtreecommitdiffstats
path: root/intl/icu/source/common/unicode/normalizer2.h
blob: 6a7668bfd5ff3e3f002c05cd8e7cdd82bbbca11c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
// Copyright (C) 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
*
*   Copyright (C) 2009-2013, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
*******************************************************************************
*   file name:  normalizer2.h
*   encoding:   US-ASCII
*   tab size:   8 (not used)
*   indentation:4
*
*   created on: 2009nov22
*   created by: Markus W. Scherer
*/

#ifndef __NORMALIZER2_H__
#define __NORMALIZER2_H__

/**
 * \file
 * \brief C++ API: New API for Unicode Normalization.
 */

#include "unicode/utypes.h"

#if !UCONFIG_NO_NORMALIZATION

#include "unicode/uniset.h"
#include "unicode/unistr.h"
#include "unicode/unorm2.h"

U_NAMESPACE_BEGIN

/**
 * Unicode normalization functionality for standard Unicode normalization or
 * for using custom mapping tables.
 * All instances of this class are unmodifiable/immutable.
 * Instances returned by getInstance() are singletons that must not be deleted by the caller.
 * The Normalizer2 class is not intended for public subclassing.
 *
 * The primary functions are to produce a normalized string and to detect whether
 * a string is already normalized.
 * The most commonly used normalization forms are those defined in
 * http://www.unicode.org/unicode/reports/tr15/
 * However, this API supports additional normalization forms for specialized purposes.
 * For example, NFKC_Casefold is provided via getInstance("nfkc_cf", COMPOSE)
 * and can be used in implementations of UTS #46.
 *
 * Not only are the standard compose and decompose modes supplied,
 * but additional modes are provided as documented in the Mode enum.
 *
 * Some of the functions in this class identify normalization boundaries.
 * At a normalization boundary, the portions of the string
 * before it and starting from it do not interact and can be handled independently.
 *
 * The spanQuickCheckYes() stops at a normalization boundary.
 * When the goal is a normalized string, then the text before the boundary
 * can be copied, and the remainder can be processed with normalizeSecondAndAppend().
 *
 * The hasBoundaryBefore(), hasBoundaryAfter() and isInert() functions test whether
 * a character is guaranteed to be at a normalization boundary,
 * regardless of context.
 * This is used for moving from one normalization boundary to the next
 * or preceding boundary, and for performing iterative normalization.
 *
 * Iterative normalization is useful when only a small portion of a
 * longer string needs to be processed.
 * For example, in ICU, iterative normalization is used by the NormalizationTransliterator
 * (to avoid replacing already-normalized text) and ucol_nextSortKeyPart()
 * (to process only the substring for which sort key bytes are computed).
 *
 * The set of normalization boundaries returned by these functions may not be
 * complete: There may be more boundaries that could be returned.
 * Different functions may return different boundaries.
 * @stable ICU 4.4
 */
class U_COMMON_API Normalizer2 : public UObject {
public:
    /**
     * Destructor.
     * @stable ICU 4.4
     */
    ~Normalizer2();

    /**
     * Returns a Normalizer2 instance for Unicode NFC normalization.
     * Same as getInstance(NULL, "nfc", UNORM2_COMPOSE, errorCode).
     * Returns an unmodifiable singleton instance. Do not delete it.
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 49
     */
    static const Normalizer2 *
    getNFCInstance(UErrorCode &errorCode);

    /**
     * Returns a Normalizer2 instance for Unicode NFD normalization.
     * Same as getInstance(NULL, "nfc", UNORM2_DECOMPOSE, errorCode).
     * Returns an unmodifiable singleton instance. Do not delete it.
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 49
     */
    static const Normalizer2 *
    getNFDInstance(UErrorCode &errorCode);

    /**
     * Returns a Normalizer2 instance for Unicode NFKC normalization.
     * Same as getInstance(NULL, "nfkc", UNORM2_COMPOSE, errorCode).
     * Returns an unmodifiable singleton instance. Do not delete it.
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 49
     */
    static const Normalizer2 *
    getNFKCInstance(UErrorCode &errorCode);

    /**
     * Returns a Normalizer2 instance for Unicode NFKD normalization.
     * Same as getInstance(NULL, "nfkc", UNORM2_DECOMPOSE, errorCode).
     * Returns an unmodifiable singleton instance. Do not delete it.
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 49
     */
    static const Normalizer2 *
    getNFKDInstance(UErrorCode &errorCode);

    /**
     * Returns a Normalizer2 instance for Unicode NFKC_Casefold normalization.
     * Same as getInstance(NULL, "nfkc_cf", UNORM2_COMPOSE, errorCode).
     * Returns an unmodifiable singleton instance. Do not delete it.
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 49
     */
    static const Normalizer2 *
    getNFKCCasefoldInstance(UErrorCode &errorCode);

    /**
     * Returns a Normalizer2 instance which uses the specified data file
     * (packageName/name similar to ucnv_openPackage() and ures_open()/ResourceBundle)
     * and which composes or decomposes text according to the specified mode.
     * Returns an unmodifiable singleton instance. Do not delete it.
     *
     * Use packageName=NULL for data files that are part of ICU's own data.
     * Use name="nfc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFC/NFD.
     * Use name="nfkc" and UNORM2_COMPOSE/UNORM2_DECOMPOSE for Unicode standard NFKC/NFKD.
     * Use name="nfkc_cf" and UNORM2_COMPOSE for Unicode standard NFKC_CF=NFKC_Casefold.
     *
     * @param packageName NULL for ICU built-in data, otherwise application data package name
     * @param name "nfc" or "nfkc" or "nfkc_cf" or name of custom data file
     * @param mode normalization mode (compose or decompose etc.)
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return the requested Normalizer2, if successful
     * @stable ICU 4.4
     */
    static const Normalizer2 *
    getInstance(const char *packageName,
                const char *name,
                UNormalization2Mode mode,
                UErrorCode &errorCode);

    /**
     * Returns the normalized form of the source string.
     * @param src source string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return normalized src
     * @stable ICU 4.4
     */
    UnicodeString
    normalize(const UnicodeString &src, UErrorCode &errorCode) const {
        UnicodeString result;
        normalize(src, result, errorCode);
        return result;
    }
    /**
     * Writes the normalized form of the source string to the destination string
     * (replacing its contents) and returns the destination string.
     * The source and destination strings must be different objects.
     * @param src source string
     * @param dest destination string; its contents is replaced with normalized src
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return dest
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    normalize(const UnicodeString &src,
              UnicodeString &dest,
              UErrorCode &errorCode) const = 0;
    /**
     * Appends the normalized form of the second string to the first string
     * (merging them at the boundary) and returns the first string.
     * The result is normalized if the first string was normalized.
     * The first and second strings must be different objects.
     * @param first string, should be normalized
     * @param second string, will be normalized
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return first
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    normalizeSecondAndAppend(UnicodeString &first,
                             const UnicodeString &second,
                             UErrorCode &errorCode) const = 0;
    /**
     * Appends the second string to the first string
     * (merging them at the boundary) and returns the first string.
     * The result is normalized if both the strings were normalized.
     * The first and second strings must be different objects.
     * @param first string, should be normalized
     * @param second string, should be normalized
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return first
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    append(UnicodeString &first,
           const UnicodeString &second,
           UErrorCode &errorCode) const = 0;

    /**
     * Gets the decomposition mapping of c.
     * Roughly equivalent to normalizing the String form of c
     * on a UNORM2_DECOMPOSE Normalizer2 instance, but much faster, and except that this function
     * returns FALSE and does not write a string
     * if c does not have a decomposition mapping in this instance's data.
     * This function is independent of the mode of the Normalizer2.
     * @param c code point
     * @param decomposition String object which will be set to c's
     *                      decomposition mapping, if there is one.
     * @return TRUE if c has a decomposition, otherwise FALSE
     * @stable ICU 4.6
     */
    virtual UBool
    getDecomposition(UChar32 c, UnicodeString &decomposition) const = 0;

    /**
     * Gets the raw decomposition mapping of c.
     *
     * This is similar to the getDecomposition() method but returns the
     * raw decomposition mapping as specified in UnicodeData.txt or
     * (for custom data) in the mapping files processed by the gennorm2 tool.
     * By contrast, getDecomposition() returns the processed,
     * recursively-decomposed version of this mapping.
     *
     * When used on a standard NFKC Normalizer2 instance,
     * getRawDecomposition() returns the Unicode Decomposition_Mapping (dm) property.
     *
     * When used on a standard NFC Normalizer2 instance,
     * it returns the Decomposition_Mapping only if the Decomposition_Type (dt) is Canonical (Can);
     * in this case, the result contains either one or two code points (=1..4 UChars).
     *
     * This function is independent of the mode of the Normalizer2.
     * The default implementation returns FALSE.
     * @param c code point
     * @param decomposition String object which will be set to c's
     *                      raw decomposition mapping, if there is one.
     * @return TRUE if c has a decomposition, otherwise FALSE
     * @stable ICU 49
     */
    virtual UBool
    getRawDecomposition(UChar32 c, UnicodeString &decomposition) const;

    /**
     * Performs pairwise composition of a & b and returns the composite if there is one.
     *
     * Returns a composite code point c only if c has a two-way mapping to a+b.
     * In standard Unicode normalization, this means that
     * c has a canonical decomposition to a+b
     * and c does not have the Full_Composition_Exclusion property.
     *
     * This function is independent of the mode of the Normalizer2.
     * The default implementation returns a negative value.
     * @param a A (normalization starter) code point.
     * @param b Another code point.
     * @return The non-negative composite code point if there is one; otherwise a negative value.
     * @stable ICU 49
     */
    virtual UChar32
    composePair(UChar32 a, UChar32 b) const;

    /**
     * Gets the combining class of c.
     * The default implementation returns 0
     * but all standard implementations return the Unicode Canonical_Combining_Class value.
     * @param c code point
     * @return c's combining class
     * @stable ICU 49
     */
    virtual uint8_t
    getCombiningClass(UChar32 c) const;

    /**
     * Tests if the string is normalized.
     * Internally, in cases where the quickCheck() method would return "maybe"
     * (which is only possible for the two COMPOSE modes) this method
     * resolves to "yes" or "no" to provide a definitive result,
     * at the cost of doing more work in those cases.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return TRUE if s is normalized
     * @stable ICU 4.4
     */
    virtual UBool
    isNormalized(const UnicodeString &s, UErrorCode &errorCode) const = 0;

    /**
     * Tests if the string is normalized.
     * For the two COMPOSE modes, the result could be "maybe" in cases that
     * would take a little more work to resolve definitively.
     * Use spanQuickCheckYes() and normalizeSecondAndAppend() for a faster
     * combination of quick check + normalization, to avoid
     * re-checking the "yes" prefix.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return UNormalizationCheckResult
     * @stable ICU 4.4
     */
    virtual UNormalizationCheckResult
    quickCheck(const UnicodeString &s, UErrorCode &errorCode) const = 0;

    /**
     * Returns the end of the normalized substring of the input string.
     * In other words, with <code>end=spanQuickCheckYes(s, ec);</code>
     * the substring <code>UnicodeString(s, 0, end)</code>
     * will pass the quick check with a "yes" result.
     *
     * The returned end index is usually one or more characters before the
     * "no" or "maybe" character: The end index is at a normalization boundary.
     * (See the class documentation for more about normalization boundaries.)
     *
     * When the goal is a normalized string and most input strings are expected
     * to be normalized already, then call this method,
     * and if it returns a prefix shorter than the input string,
     * copy that prefix and use normalizeSecondAndAppend() for the remainder.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return "yes" span end index
     * @stable ICU 4.4
     */
    virtual int32_t
    spanQuickCheckYes(const UnicodeString &s, UErrorCode &errorCode) const = 0;

    /**
     * Tests if the character always has a normalization boundary before it,
     * regardless of context.
     * If true, then the character does not normalization-interact with
     * preceding characters.
     * In other words, a string containing this character can be normalized
     * by processing portions before this character and starting from this
     * character independently.
     * This is used for iterative normalization. See the class documentation for details.
     * @param c character to test
     * @return TRUE if c has a normalization boundary before it
     * @stable ICU 4.4
     */
    virtual UBool hasBoundaryBefore(UChar32 c) const = 0;

    /**
     * Tests if the character always has a normalization boundary after it,
     * regardless of context.
     * If true, then the character does not normalization-interact with
     * following characters.
     * In other words, a string containing this character can be normalized
     * by processing portions up to this character and after this
     * character independently.
     * This is used for iterative normalization. See the class documentation for details.
     * Note that this operation may be significantly slower than hasBoundaryBefore().
     * @param c character to test
     * @return TRUE if c has a normalization boundary after it
     * @stable ICU 4.4
     */
    virtual UBool hasBoundaryAfter(UChar32 c) const = 0;

    /**
     * Tests if the character is normalization-inert.
     * If true, then the character does not change, nor normalization-interact with
     * preceding or following characters.
     * In other words, a string containing this character can be normalized
     * by processing portions before this character and after this
     * character independently.
     * This is used for iterative normalization. See the class documentation for details.
     * Note that this operation may be significantly slower than hasBoundaryBefore().
     * @param c character to test
     * @return TRUE if c is normalization-inert
     * @stable ICU 4.4
     */
    virtual UBool isInert(UChar32 c) const = 0;
};

/**
 * Normalization filtered by a UnicodeSet.
 * Normalizes portions of the text contained in the filter set and leaves
 * portions not contained in the filter set unchanged.
 * Filtering is done via UnicodeSet::span(..., USET_SPAN_SIMPLE).
 * Not-in-the-filter text is treated as "is normalized" and "quick check yes".
 * This class implements all of (and only) the Normalizer2 API.
 * An instance of this class is unmodifiable/immutable but is constructed and
 * must be destructed by the owner.
 * @stable ICU 4.4
 */
class U_COMMON_API FilteredNormalizer2 : public Normalizer2 {
public:
    /**
     * Constructs a filtered normalizer wrapping any Normalizer2 instance
     * and a filter set.
     * Both are aliased and must not be modified or deleted while this object
     * is used.
     * The filter set should be frozen; otherwise the performance will suffer greatly.
     * @param n2 wrapped Normalizer2 instance
     * @param filterSet UnicodeSet which determines the characters to be normalized
     * @stable ICU 4.4
     */
    FilteredNormalizer2(const Normalizer2 &n2, const UnicodeSet &filterSet) :
            norm2(n2), set(filterSet) {}

    /**
     * Destructor.
     * @stable ICU 4.4
     */
    ~FilteredNormalizer2();

    /**
     * Writes the normalized form of the source string to the destination string
     * (replacing its contents) and returns the destination string.
     * The source and destination strings must be different objects.
     * @param src source string
     * @param dest destination string; its contents is replaced with normalized src
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return dest
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    normalize(const UnicodeString &src,
              UnicodeString &dest,
              UErrorCode &errorCode) const;
    /**
     * Appends the normalized form of the second string to the first string
     * (merging them at the boundary) and returns the first string.
     * The result is normalized if the first string was normalized.
     * The first and second strings must be different objects.
     * @param first string, should be normalized
     * @param second string, will be normalized
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return first
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    normalizeSecondAndAppend(UnicodeString &first,
                             const UnicodeString &second,
                             UErrorCode &errorCode) const;
    /**
     * Appends the second string to the first string
     * (merging them at the boundary) and returns the first string.
     * The result is normalized if both the strings were normalized.
     * The first and second strings must be different objects.
     * @param first string, should be normalized
     * @param second string, should be normalized
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return first
     * @stable ICU 4.4
     */
    virtual UnicodeString &
    append(UnicodeString &first,
           const UnicodeString &second,
           UErrorCode &errorCode) const;

    /**
     * Gets the decomposition mapping of c.
     * For details see the base class documentation.
     *
     * This function is independent of the mode of the Normalizer2.
     * @param c code point
     * @param decomposition String object which will be set to c's
     *                      decomposition mapping, if there is one.
     * @return TRUE if c has a decomposition, otherwise FALSE
     * @stable ICU 4.6
     */
    virtual UBool
    getDecomposition(UChar32 c, UnicodeString &decomposition) const;

    /**
     * Gets the raw decomposition mapping of c.
     * For details see the base class documentation.
     *
     * This function is independent of the mode of the Normalizer2.
     * @param c code point
     * @param decomposition String object which will be set to c's
     *                      raw decomposition mapping, if there is one.
     * @return TRUE if c has a decomposition, otherwise FALSE
     * @stable ICU 49
     */
    virtual UBool
    getRawDecomposition(UChar32 c, UnicodeString &decomposition) const;

    /**
     * Performs pairwise composition of a & b and returns the composite if there is one.
     * For details see the base class documentation.
     *
     * This function is independent of the mode of the Normalizer2.
     * @param a A (normalization starter) code point.
     * @param b Another code point.
     * @return The non-negative composite code point if there is one; otherwise a negative value.
     * @stable ICU 49
     */
    virtual UChar32
    composePair(UChar32 a, UChar32 b) const;

    /**
     * Gets the combining class of c.
     * The default implementation returns 0
     * but all standard implementations return the Unicode Canonical_Combining_Class value.
     * @param c code point
     * @return c's combining class
     * @stable ICU 49
     */
    virtual uint8_t
    getCombiningClass(UChar32 c) const;

    /**
     * Tests if the string is normalized.
     * For details see the Normalizer2 base class documentation.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return TRUE if s is normalized
     * @stable ICU 4.4
     */
    virtual UBool
    isNormalized(const UnicodeString &s, UErrorCode &errorCode) const;
    /**
     * Tests if the string is normalized.
     * For details see the Normalizer2 base class documentation.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return UNormalizationCheckResult
     * @stable ICU 4.4
     */
    virtual UNormalizationCheckResult
    quickCheck(const UnicodeString &s, UErrorCode &errorCode) const;
    /**
     * Returns the end of the normalized substring of the input string.
     * For details see the Normalizer2 base class documentation.
     * @param s input string
     * @param errorCode Standard ICU error code. Its input value must
     *                  pass the U_SUCCESS() test, or else the function returns
     *                  immediately. Check for U_FAILURE() on output or use with
     *                  function chaining. (See User Guide for details.)
     * @return "yes" span end index
     * @stable ICU 4.4
     */
    virtual int32_t
    spanQuickCheckYes(const UnicodeString &s, UErrorCode &errorCode) const;

    /**
     * Tests if the character always has a normalization boundary before it,
     * regardless of context.
     * For details see the Normalizer2 base class documentation.
     * @param c character to test
     * @return TRUE if c has a normalization boundary before it
     * @stable ICU 4.4
     */
    virtual UBool hasBoundaryBefore(UChar32 c) const;

    /**
     * Tests if the character always has a normalization boundary after it,
     * regardless of context.
     * For details see the Normalizer2 base class documentation.
     * @param c character to test
     * @return TRUE if c has a normalization boundary after it
     * @stable ICU 4.4
     */
    virtual UBool hasBoundaryAfter(UChar32 c) const;

    /**
     * Tests if the character is normalization-inert.
     * For details see the Normalizer2 base class documentation.
     * @param c character to test
     * @return TRUE if c is normalization-inert
     * @stable ICU 4.4
     */
    virtual UBool isInert(UChar32 c) const;
private:
    UnicodeString &
    normalize(const UnicodeString &src,
              UnicodeString &dest,
              USetSpanCondition spanCondition,
              UErrorCode &errorCode) const;

    UnicodeString &
    normalizeSecondAndAppend(UnicodeString &first,
                             const UnicodeString &second,
                             UBool doNormalize,
                             UErrorCode &errorCode) const;

    const Normalizer2 &norm2;
    const UnicodeSet &set;
};

U_NAMESPACE_END

#endif  // !UCONFIG_NO_NORMALIZATION
#endif  // __NORMALIZER2_H__