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1# Copyright (C) 2016 and later: Unicode, Inc. and others.
2# License & terms of use: http://www.unicode.org/copyright.html
3# Copyright (c) 2002-2016  International Business Machines Corporation and
4# others. All Rights Reserved.
5#
6#  file:  line_normal_cj.txt
7#
8#         Line Breaking Rules
9#         Implement default line breaking as defined by
10#         Unicode Standard Annex #14 Revision 37 for Unicode 9.0
11#         http://www.unicode.org/reports/tr14/
12#
13#         Includes extensions to the handling of emoji ZWJ sequences from
14#         https://goo.gl/cluFCn
15#
16#         tailored as noted in 2nd paragraph below.
17#
18#         TODO:  Rule LB 8 remains as it was in Unicode 5.2
19#         This is only because of a limitation of ICU break engine implementation,
20#         not because the older behavior is desirable.
21#
22#         This tailors the line break behavior to correspond to CSS
23#         line-break=normal (BCP47 -u-lb-normal) as defined for Chinese & Japanese.
24#         It sets characters of class CJ to behave like ID.
25#         In addition, it allows breaks:
26#         * before hyphens 2010 & 2013 (both BA) and 301C, 30A0 (both NS)
27
28#
29#  Character Classes defined by TR 14.
30#
31
32!!chain;
33
34$AI = [:LineBreak =  Ambiguous:];
35$AL = [:LineBreak =  Alphabetic:];
36$BAX = [\u2010 \u2013];
37$BA = [[:LineBreak =  Break_After:] - $BAX];
38$BB = [:LineBreak =  Break_Before:];
39$BK = [:LineBreak =  Mandatory_Break:];
40$B2 = [:LineBreak =  Break_Both:];
41$CB = [:LineBreak =  Contingent_Break:];
42$CJ = [:LineBreak =  Conditional_Japanese_Starter:];
43$CL = [:LineBreak =  Close_Punctuation:];
44# $CM = [:LineBreak =  Combining_Mark:];
45$CP = [:LineBreak =  Close_Parenthesis:];
46$CR = [:LineBreak =  Carriage_Return:];
47$EB = [[:LineBreak =  EB:]\U0001F3C2\U0001F3C7\U0001F3CC\U0001F46A-\U0001F46D\U0001F46F\U0001F574\U0001F6CC];
48$EM = [:LineBreak =  EM:];
49$EX = [:LineBreak =  Exclamation:];
50$GL = [:LineBreak =  Glue:];
51$HL = [:LineBreak =  Hebrew_Letter:];
52$HY = [:LineBreak =  Hyphen:];
53$H2 = [:LineBreak =  H2:];
54$H3 = [:LineBreak =  H3:];
55# CSS Normal tailoring: CJ resolves to ID
56$ID = [[:LineBreak =  Ideographic:] $CJ];
57$IN = [:LineBreak =  Inseperable:];
58$IS = [:LineBreak =  Infix_Numeric:];
59$JL = [:LineBreak =  JL:];
60$JV = [:LineBreak =  JV:];
61$JT = [:LineBreak =  JT:];
62$LF = [:LineBreak =  Line_Feed:];
63$NL = [:LineBreak =  Next_Line:];
64$NSX = [\u301C \u30A0];
65$NS = [[:LineBreak =  Nonstarter:] - $NSX];
66$NU = [:LineBreak =  Numeric:];
67$OP = [:LineBreak =  Open_Punctuation:];
68$PO = [:LineBreak =  Postfix_Numeric:];
69$PR = [:LineBreak =  Prefix_Numeric:];
70$QU = [:LineBreak =  Quotation:];
71$RI = [:LineBreak =  Regional_Indicator:];
72$SA = [:LineBreak =  Complex_Context:];
73$SG = [:LineBreak =  Surrogate:];
74$SP = [:LineBreak =  Space:];
75$SY = [:LineBreak =  Break_Symbols:];
76$WJ = [:LineBreak =  Word_Joiner:];
77$XX = [:LineBreak =  Unknown:];
78$ZW = [:LineBreak =  ZWSpace:];
79$ZWJ = [:LineBreak = ZWJ:];
80
81$EmojiNRK = [[\p{Emoji}] - [$RI \u002a\u00230-9©®™〰〽]];
82# Data for Extended Pictographic scraped from CLDR common/properties/ExtendedPictographic.txt, r12773
83$Extended_Pict = [\U0001F774-\U0001F77F\u2700-\u2701\u2703-\u2704\u270E\u2710-\u2711\u2765-\u2767\U0001F030-\U0001F093\U0001F094-\U0001F09F\U0001F10D-\U0001F10F\U0001F12F\U0001F16C-\U0001F16F\U0001F1AD-\U0001F1E5\U0001F203-\U0001F20F\U0001F23C-\U0001F23F\U0001F249-\U0001F24F\U0001F252-\U0001F2FF\U0001F7D5-\U0001F7FF\U0001F000-\U0001F003\U0001F005-\U0001F02B\U0001F02C-\U0001F02F\U0001F322-\U0001F323\U0001F394-\U0001F395\U0001F398\U0001F39C-\U0001F39D\U0001F3F1-\U0001F3F2\U0001F3F6\U0001F4FE\U0001F53E-\U0001F548\U0001F54F\U0001F568-\U0001F56E\U0001F571-\U0001F572\U0001F57B-\U0001F586\U0001F588-\U0001F589\U0001F58E-\U0001F58F\U0001F591-\U0001F594\U0001F597-\U0001F5A3\U0001F5A6-\U0001F5A7\U0001F5A9-\U0001F5B0\U0001F5B3-\U0001F5BB\U0001F5BD-\U0001F5C1\U0001F5C5-\U0001F5D0\U0001F5D4-\U0001F5DB\U0001F5DF-\U0001F5E0\U0001F5E2\U0001F5E4-\U0001F5E7\U0001F5E9-\U0001F5EE\U0001F5F0-\U0001F5F2\U0001F5F4-\U0001F5F9\u2605\u2607-\u260D\u260F-\u2610\u2612\u2616-\u2617\u2619-\u261C\u261E-\u261F\u2621\u2624-\u2625\u2627-\u2629\u262B-\u262D\u2630-\u2637\u263B-\u2647\u2654-\u265F\u2661-\u2662\u2664\u2667\u2669-\u267A\u267C-\u267E\u2680-\u2691\u2695\u2698\u269A\u269D-\u269F\u26A2-\u26A9\u26AC-\u26AF\u26B2-\u26BC\u26BF-\u26C3\u26C6-\u26C7\u26C9-\u26CD\u26D0\u26D2\u26D5-\u26E8\u26EB-\u26EF\u26F6\u26FB-\u26FC\u26FE-\u26FF\u2388\U0001FA00-\U0001FFFD\U0001F0A0-\U0001F0AE\U0001F0B1-\U0001F0BF\U0001F0C1-\U0001F0CF\U0001F0D1-\U0001F0F5\U0001F0AF-\U0001F0B0\U0001F0C0\U0001F0D0\U0001F0F6-\U0001F0FF\U0001F80C-\U0001F80F\U0001F848-\U0001F84F\U0001F85A-\U0001F85F\U0001F888-\U0001F88F\U0001F8AE-\U0001F8FF\U0001F900-\U0001F90F\U0001F91F\U0001F928-\U0001F92F\U0001F931-\U0001F932\U0001F93F\U0001F94C-\U0001F94F\U0001F95F-\U0001F97F\U0001F992-\U0001F9BF\U0001F9C1-\U0001F9FF\U0001F6C6-\U0001F6CA\U0001F6E6-\U0001F6E8\U0001F6EA\U0001F6F1-\U0001F6F2\U0001F6D3-\U0001F6DF\U0001F6ED-\U0001F6EF\U0001F6F7-\U0001F6FF];
84
85# By LB9, a ZWJ also behaves as a CM. Including it in the definition of CM avoids having to explicitly
86#         list it in the numerous rules that use CM.
87# By LB1, SA characters with general categor of Mn or Mc also resolve to CM.
88
89$CM = [[:LineBreak = Combining_Mark:] $ZWJ [$SA & [[:Mn:][:Mc:]]]];
90
91#   Dictionary character set, for triggering language-based break engines. Currently
92#   limited to LineBreak=Complex_Context (SA).
93
94$dictionary = [$SA];
95
96#
97#  Rule LB1.  By default, treat AI  (characters with ambiguous east Asian width),
98#                               SA  (Dictionary chars, excluding Mn and Mc)
99#                               SG  (Unpaired Surrogates)
100#                               XX  (Unknown, unassigned)
101#                         as $AL  (Alphabetic)
102#
103$ALPlus = [$AL $AI $SG $XX [$SA-[[:Mn:][:Mc:]]]];
104
105
106## -------------------------------------------------
107
108!!forward;
109
110#
111# CAN_CM  is the set of characters that may combine with CM combining chars.
112#         Note that Linebreak UAX 14's concept of a combining char and the rules
113#         for what they can combine with are _very_ different from the rest of Unicode.
114#
115#         Note that $CM itself is left out of this set.  If CM is needed as a base
116#         it must be listed separately in the rule.
117#
118$CAN_CM  = [^$SP $BK $CR $LF $NL $ZW $CM];       # Bases that can   take CMs
119$CANT_CM = [ $SP $BK $CR $LF $NL $ZW $CM];       # Bases that can't take CMs
120
121#
122# AL_FOLLOW  set of chars that can unconditionally follow an AL
123#            Needed in rules where stand-alone $CM s are treated as AL.
124#
125$AL_FOLLOW      = [$BK $CR $LF $NL $ZW $SP $CL $CP $EX $HL $IS $SY $WJ $GL $OP $QU $BA $HY $NS $IN $NU $PR $PO $ALPlus];
126
127
128#
129#  Rule LB 4, 5    Mandatory (Hard) breaks.
130#
131$LB4Breaks    = [$BK $CR $LF $NL];
132$LB4NonBreaks = [^$BK $CR $LF $NL $CM];
133$CR $LF {100};
134
135#
136#  LB 6    Do not break before hard line breaks.
137#
138$LB4NonBreaks?  $LB4Breaks {100};    # LB 5  do not break before hard breaks.
139$CAN_CM $CM*    $LB4Breaks {100};
140^$CM+           $LB4Breaks {100};
141
142# LB 7         x SP
143#              x ZW
144$LB4NonBreaks [$SP $ZW];
145$CAN_CM $CM*  [$SP $ZW];
146^$CM+         [$SP $ZW];
147
148#
149# LB 8         Break after zero width space
150#              TODO:  ZW SP* <break>
151#              An engine change is required to write the reverse rule for this.
152#              For now, leave the Unicode 5.2 rule, ZW <break>
153#
154$LB8Breaks    = [$LB4Breaks $ZW];
155$LB8NonBreaks = [[$LB4NonBreaks] - [$ZW]];
156
157# LB 8a        ZWJ x (ID | Extended_Pict | EmojiNRK)   Emoji ZWJ sequences.
158#
159$ZWJ ($ID | $Extended_Pict | $EmojiNRK);
160
161# LB 9     Combining marks.      X   $CM needs to behave like X, where X is not $SP, $BK $CR $LF $NL
162#                                $CM not covered by the above needs to behave like $AL
163#                                See definition of $CAN_CM.
164
165$CAN_CM $CM+;                   #  Stick together any combining sequences that don't match other rules.
166^$CM+;
167
168#
169# LB 11  Do not break before or after WORD JOINER & related characters.
170#
171$CAN_CM $CM*  $WJ;
172$LB8NonBreaks $WJ;
173^$CM+         $WJ;
174
175$WJ $CM* .;
176
177#
178# LB 12  Do not break after NBSP and related characters.
179#         GL  x
180#
181$GL $CM* .;
182
183#
184# LB 12a  Do not break before NBSP and related characters ...
185#            [^SP BA HY] x GL
186#
187[[$LB8NonBreaks] - [$SP $BA $BAX $HY]] $CM* $GL;
188^$CM+ $GL;
189
190
191
192#
193# LB 13   Don't break before ']' or '!' or ';' or '/', even after spaces.
194#
195$LB8NonBreaks $CL;
196$CAN_CM $CM*  $CL;
197^$CM+         $CL;              # by rule 10, stand-alone CM behaves as AL
198
199$LB8NonBreaks $CP;
200$CAN_CM $CM*  $CP;
201^$CM+         $CP;              # by rule 10, stand-alone CM behaves as AL
202
203$LB8NonBreaks $EX;
204$CAN_CM $CM*  $EX;
205^$CM+         $EX;              # by rule 10, stand-alone CM behaves as AL
206
207$LB8NonBreaks $IS;
208$CAN_CM $CM*  $IS;
209^$CM+         $IS;              # by rule 10, stand-alone CM behaves as AL
210
211$LB8NonBreaks $SY;
212$CAN_CM $CM*  $SY;
213^$CM+         $SY;              # by rule 10, stand-alone CM behaves as AL
214
215
216#
217# LB 14  Do not break after OP, even after spaces
218#
219$OP $CM* $SP* .;
220
221$OP $CM* $SP+ $CM+ $AL_FOLLOW?;    # by rule 10, stand-alone CM behaves as AL
222                                   # by rule 8, CM following a SP is stand-alone.
223
224# LB 15
225$QU $CM* $SP* $OP;
226
227# LB 16
228# Do not break between closing punctuation and $NS, even with intervening spaces
229# But DO allow a break between closing punctuation and $NSX, don't include it here
230($CL | $CP) $CM* $SP* $NS;
231
232# LB 17
233$B2 $CM* $SP* $B2;
234
235#
236# LB 18  Break after spaces.
237#
238$LB18NonBreaks = [$LB8NonBreaks - [$SP]];
239$LB18Breaks    = [$LB8Breaks $SP];
240
241
242# LB 19
243#         x QU
244$LB18NonBreaks $CM* $QU;
245^$CM+               $QU;
246
247#         QU  x
248$QU $CM* .;
249
250
251# LB 20
252#        <break>  $CB
253#        $CB   <break>
254
255$LB20NonBreaks = [$LB18NonBreaks - $CB];
256
257# LB 21        x   (BA | HY | NS)
258#           BB x
259#
260# DO allow breaks here before $BAXcm and $NSXcm, so don't include them
261$LB20NonBreaks $CM* ($BA | $HY | $NS);
262^$CM+ ($BA | $HY | $NS);
263
264$BB $CM* [^$CB];                                  #  $BB  x
265$BB $CM* $LB20NonBreaks;
266
267# LB 21a Don't break after Hebrew + Hyphen
268#   HL (HY | BA) x
269#
270$HL $CM* ($HY | $BA | $BAX) $CM* [^$CB]?;
271
272# LB 21b (forward) Don't break between SY and HL
273# (break between HL and SY already disallowed by LB 13 above)
274$SY $CM* $HL;
275
276# LB 22
277($ALPlus | $HL) $CM* $IN;
278^$CM+    $IN;     #  by rule 10, any otherwise unattached CM behaves as AL
279$EX $CM*    $IN;
280($ID | $EB | $EM) $CM*  $IN;
281$IN $CM*    $IN;
282$NU $CM*    $IN;
283
284
285# $LB 23
286#
287($ALPlus | $HL) $CM* $NU;
288^$CM+  $NU;       # Rule 10, any otherwise unattached CM behaves as AL
289$NU $CM* ($ALPlus | $HL);
290
291# LB 23a
292#
293$PR $CM* ($ID | $EB | $EM);
294($ID | $EB | $EM) $CM*  $PO;
295
296
297#
298# LB 24
299#
300($PR | $PO) $CM* ($ALPlus | $HL);
301($ALPlus | $HL) $CM* ($PR | $PO);
302^$CM+ ($PR | $PO);       # Rule 10, any otherwise unattached CM behaves as AL
303
304#
305# LB 25   Numbers.
306#
307(($PR | $PO) $CM*)? (($OP | $HY) $CM*)? $NU ($CM* ($NU | $SY | $IS))*
308    ($CM* ($CL | $CP))? ($CM* ($PR | $PO))?;
309
310# LB 26  Do not break a Korean syllable
311#
312$JL $CM* ($JL | $JV | $H2 | $H3);
313($JV | $H2) $CM* ($JV | $JT);
314($JT | $H3) $CM* $JT;
315
316# LB 27  Treat korean Syllable Block the same as ID  (don't break it)
317($JL | $JV | $JT | $H2 | $H3) $CM* $IN;
318($JL | $JV | $JT | $H2 | $H3) $CM* $PO;
319$PR $CM* ($JL | $JV | $JT | $H2 | $H3);
320
321
322# LB 28   Do not break between alphabetics
323#
324($ALPlus | $HL) $CM* ($ALPlus | $HL);
325^$CM+ ($ALPlus | $HL);      # The $CM+ is from rule 10, an unattached CM is treated as AL
326
327# LB 29
328$IS $CM* ($ALPlus | $HL);
329
330# LB 30
331($ALPlus | $HL | $NU) $CM* $OP;
332^$CM+ $OP;         # The $CM+ is from rule 10, an unattached CM is treated as AL.
333$CP $CM* ($ALPlus | $HL | $NU);
334
335# LB 30a  Do not break between regional indicators. Break after pairs of them.
336#         Tricky interaction with LB8a: ZWJ x ID
337$RI $CM* $RI                / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM] {eof}];
338$RI $CM* $RI $CM*  $ZWJ     / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM $ID $Extended_Pict $EmojiNRK] {eof}];
339$RI $CM* $RI $CM* [$CM-$ZWJ] / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM] {eof}];
340
341$RI $CM* $RI $CM* [$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS {eof}];
342$RI $CM* $RI $CM* $ZWJ ($ID | $Extended_Pict | $EmojiNRK);
343
344# LB 30b Do not break between an Emoji Base and an Emoji Modifier
345$EB $CM* $EM;
346
347#
348#  Reverse Rules.
349#
350## -------------------------------------------------
351
352!!reverse;
353
354#  LB 9 Combining Marks.
355#  Stick together any combining sequences that don't match other rules.
356
357^$CM+ $CAN_CM?;
358
359#
360#  Sequences of the form  (shown forwards)
361#      [CANT_CM]  <break>  [CM]  [whatever]
362#  The CM needs to behave as an AL
363#
364$AL_FOLLOW $CM+ / (
365          [$BK $CR $LF $NL $ZW {eof}] |
366          $SP+ $CM+ $SP |
367          $SP+ $CM* ([^$OP $CM $SP] | [$AL {eof}]));   # if LB 14 will match, need to surpress this break.
368                                               #  LB14 says    OP SP* x .
369                                               #    becomes    OP SP* x AL
370                                               #    becomes    OP SP* x CM+ AL_FOLLOW
371                                               #
372                                               # Further note:  the $AL in [$AL {eof}] is only to work around
373                                               #                a rule compiler bug which complains about
374                                               #                empty sets otherwise.
375
376
377# LB 4, 5, 6
378
379$LB4Breaks [$LB4NonBreaks-$CM];
380$LB4Breaks $CM+ $CAN_CM;
381$LF $CR;
382
383
384# LB 7         x SP
385#              x ZW
386[$SP $ZW] [$LB4NonBreaks-$CM];
387[$SP $ZW] $CM+ $CAN_CM;
388
389# LB 8 ZW SP* <break>
390#     TODO: to implement this, we need more than one look-ahead hard break in play at a time.
391#           Requires an engine enhancement.
392#   / $SP* $ZW
393
394# LB 8a        ZWJ x (ID | Extended_Pict | EmojiNRK)
395#
396($ID | $Extended_Pict | $EmojiNRK) $ZWJ $CM* $CAN_CM?;
397
398
399# LB 9,10  Combining marks.
400#    X   $CM needs to behave like X, where X is not $SP or controls.
401#    $CM not covered by the above needs to behave like $AL
402# Stick together any combining sequences that don't match other rules.
403^$CM+ $CAN_CM;
404
405
406# LB 11
407#
408$WJ $CM* $CAN_CM;
409$WJ      [$LB8NonBreaks-$CM];
410
411     $CANT_CM $CM* $WJ;
412$CAN_CM  $CM* $WJ;
413
414# LB 12a
415#      [^SP BA HY] x GL
416#
417$GL $CM* [$LB8NonBreaks-[$CM $SP $BA $BAX $HY]];
418
419# LB 12
420#     GL  x
421#
422$CANT_CM $CM* $GL;
423$CAN_CM $CM* $GL;
424
425
426# LB 13
427$CL $CM+ $CAN_CM;
428$CP $CM+ $CAN_CM;
429$EX $CM+ $CAN_CM;
430$IS $CM+ $CAN_CM;
431$SY $CM+ $CAN_CM;
432
433$CL [$LB8NonBreaks-$CM];
434$CP [$LB8NonBreaks-$CM];
435$EX [$LB8NonBreaks-$CM];
436$IS [$LB8NonBreaks-$CM];
437$SY [$LB8NonBreaks-$CM];
438
439
440# LB 14    OP SP* x
441#
442.   $SP* $CM* $OP;
443$AL_FOLLOW? $CM+ $SP+ $CM* $OP;     #  by LB 10, behaves like $AL_FOLLOW? $AL $SP+ $CM* $OP
444
445
446# LB 15
447$OP $SP* $CM* $QU;
448
449# LB 16
450# Don't include $NSX here
451$NS $SP* $CM* ($CL | $CP);
452
453# LB 17
454$B2 $SP* $CM* $B2;
455
456# LB 18  break after spaces
457#        Nothing explicit needed here.
458
459
460#
461# LB 19
462#
463$QU $CM* $CAN_CM;                                #   . x QU
464$QU      $LB18NonBreaks;
465
466
467$CAN_CM  $CM* $QU;                               #   QU x .
468     $CANT_CM $CM* $QU;
469
470#
471#  LB 20  Break before and after CB.
472#         nothing needed here.
473#
474
475# LB 21
476# Don't include $BAX or $NSX here
477($BA | $HY | $NS) $CM* [$LB20NonBreaks-$CM];     #  . x (BA | HY | NS)
478
479[$LB20NonBreaks-$CM] $CM* $BB;                   #  BB x .
480[^$CB] $CM* $BB;                                      #
481
482# LB21a  Don't break after Hebrew + Hyphen.
483([^$CB] $CM*)? ($HY | $BA | $BAX) $CM* $HL;
484
485# LB21b (reverse)
486$HL $CM* $SY;
487
488# LB 22
489$IN $CM* ($ALPlus | $HL);
490$IN $CM* $EX;
491$IN $CM* ($ID | $EB | $EM);
492$IN $CM* $IN;
493$IN $CM* $NU;
494
495# LB 23
496$NU $CM* ($ALPlus | $HL);
497($ALPlus | $HL) $CM* $NU;
498
499# LB23a
500($ID | $EB | $EM) $CM* $PR;
501$PO $CM* ($ID | $EB | $EM);
502
503# LB 24
504($ALPlus | $HL) $CM* ($PR | $PO);
505($PR | $PO) $CM* ($ALPlus | $HL);
506
507
508# LB 25
509($CM* ($PR | $PO))? ($CM* ($CL | $CP))? ($CM* ($NU | $IS | $SY))* $CM* $NU ($CM* ($OP | $HY))? ($CM* ($PR | $PO))?;
510
511# LB 26
512($H3 | $H2 | $JV | $JL) $CM* $JL;
513($JT | $JV) $CM* ($H2 | $JV);
514$JT $CM* ($H3 | $JT);
515
516# LB 27
517$IN $CM* ($H3 | $H2 | $JT | $JV | $JL);
518$PO $CM* ($H3 | $H2 | $JT | $JV | $JL);
519 ($H3 | $H2 | $JT | $JV | $JL) $CM* $PR;
520
521# LB 28
522($ALPlus | $HL) $CM* ($ALPlus | $HL);
523
524
525# LB 29
526($ALPlus | $HL) $CM* $IS;
527
528# LB 30
529$OP $CM* ($ALPlus | $HL | $NU);
530($ALPlus | $HL | $NU) $CM* $CP;
531
532# LB 30a
533#    Pairs of Regional Indicators.
534#    The following two rules are nearly identical. The first matches only sequences with an odd number of adjacent RIs,
535#    the second with an even number. Stripping away the cruft they look like
536#         [^RI] RI / (RI RI)+ ^RI;
537#         [^RI] RI RI / (RI RI)+ ^RI;
538#
539[{bof} $NS $HY $BA $QU $CL $CP $EX $IS $SY $WJ $GL $ZW $SP $BK $CR $LF $NL $ZWJ] $CM* $RI / ($CM* $RI $CM* $RI)+ $CM* [{eof}[^$RI $CM]];
540[{bof} $NS $HY $BA $QU $CL $CP $EX $IS $SY $WJ $GL $ZW $SP $BK $CR $LF $NL $ZWJ] $CM* $RI $CM* $RI / ($CM* $RI $CM* $RI)+ $CM* [{eof}[^$RI $CM]];
541
542# In general, adjacent RIs stay together. The hard-break rules, above, overide this, forcing in the boundaries between pairs.
543$RI $CM* $RI;
544
545#    WJ, GL, QU, etc. are classes with rules like "WJ x "   which includes "WJ x RI".
546$RI $CM* ([$WJ $GL $QU $BB] |  (($HY | $BA)$CM* $HL));
547
548
549# LB 30b Do not break between an Emoji Base and an Emoji Modifier
550$EM $CM* $EB;
551
552
553## -------------------------------------------------
554
555!!safe_reverse;
556
557# LB 9
558^$CM+ [^$CM $BK $CR $LF $NL $ZW $SP];
559^$CM+ $SP / .;
560
561# LB 14
562$SP+ $CM* $OP;
563
564# LB 15
565$SP+ $CM* $QU;
566
567# LB 16
568$SP+ $CM* ($CL | $CP);
569
570# LB 17
571$SP+ $CM* $B2;
572
573# LB 21
574$CM* ($HY | $BA | $BAX) $CM* $HL;
575
576# LB 25
577($CM* ($IS | $SY))+ $CM* $NU;
578($CL | $CP) $CM* ($NU | $IS | $SY);
579
580#  LB 30
581($CM* $RI)+;
582
583# For dictionary-based break
584$dictionary $dictionary;
585
586## -------------------------------------------------
587
588!!safe_forward;
589
590# Skip forward over all character classes that are involved in
591#   rules containing patterns with possibly more than one char
592#   of context.
593#
594#  It might be slightly more efficient to have specific rules
595#  instead of one generic one, but only if we could
596#  turn off rule chaining.  We don't want to move more
597#  than necessary.
598#
599^[$CM $OP $QU $CL $CP $B2 $PR $HY $BA $BAX $SP $RI $ZWJ $dictionary]+ [^$CM $OP $QU $CL $CP $B2 $PR $HY $BA $BAX $RI $ZWJ $dictionary];
600$dictionary $dictionary;
601
602