icuSources/data/brkitr/rules/line_loose_cj.txt

   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_loose_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=loose (BCP47 -u-lb-loose) 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 #         * before iteration marks 3005, 303B, 309D, 309E, 30FD, 30FE (all NS)
  28 #         * between characters of LineBreak class IN such as 2026
  29 #         * before some centered punct 203C, 2047, 2048, 2049, 30FB, FF1A, FF1B,
  30 #           FF65 (all NS) and FF01, FF1F (both EX).
  31 #         * before suffix characters with LineBreak class PO and EastAsianWidth A,F,W;
  32 #           this includes: 00B0 2030 2032 2033 2035 2103 2109 FE6A FF05 FFE0
  33 #         * after prefix characters with LineBreak class PR and EastAsianWidth A,F,W;
  34 #           this includes: 00A4 00B1 20AC 2116 FE69 FF04 FFE1 FFE5 FFE6
  35
  36
  37 #
  38 #  Character Classes defined by TR 14.
  39 #
  40
  41 !!chain;
  42
  43 $AI = [:LineBreak =  Ambiguous:];
  44 $AL = [:LineBreak =  Alphabetic:];
  45 $BAX = [\u2010 \u2013];
  46 $BA = [[:LineBreak =  Break_After:] - $BAX];
  47 $BB = [:LineBreak =  Break_Before:];
  48 $BK = [:LineBreak =  Mandatory_Break:];
  49 $B2 = [:LineBreak =  Break_Both:];
  50 $CB = [:LineBreak =  Contingent_Break:];
  51 $CJ = [:LineBreak =  Conditional_Japanese_Starter:];
  52 $CL = [:LineBreak =  Close_Punctuation:];
  53 # $CM = [:LineBreak =  Combining_Mark:];
  54 $CP = [:LineBreak =  Close_Parenthesis:];
  55 $CR = [:LineBreak =  Carriage_Return:];
  56 $EB = [[:LineBreak =  EB:] \U0001F46A-\U0001F46D\U0001F46F\U0001F91D\U0001F93C];
  57 $EM = [:LineBreak =  EM:];
  58 $EXX = [\uFF01 \uFF1F];
  59 $EX = [[:LineBreak =  Exclamation:] - $EXX];
  60 $GL = [:LineBreak =  Glue:];
  61 $HL = [:LineBreak =  Hebrew_Letter:];
  62 $HY = [:LineBreak =  Hyphen:];
  63 $H2 = [:LineBreak =  H2:];
  64 $H3 = [:LineBreak =  H3:];
  65 # CSS Loose tailoring: CJ resolves to ID
  66 $ID = [[:LineBreak =  Ideographic:] $CJ];
  67 $IN = [:LineBreak =  Inseperable:];
  68 $IS = [:LineBreak =  Infix_Numeric:];
  69 $JL = [:LineBreak =  JL:];
  70 $JV = [:LineBreak =  JV:];
  71 $JT = [:LineBreak =  JT:];
  72 $LF = [:LineBreak =  Line_Feed:];
  73 $NL = [:LineBreak =  Next_Line:];
  74 $NSX = [\u301C \u30A0 \u3005 \u303B \u309D \u309E \u30FD \u30FE \u203C \u2047 \u2048 \u2049 \u30FB \uFF1A \uFF1B \uFF65];
  75 $NS = [[:LineBreak =  Nonstarter:] - $NSX];
  76 $NU = [:LineBreak =  Numeric:];
  77 $OP = [:LineBreak =  Open_Punctuation:];
  78 $POX = [\u00B0 \u2030 \u2032 \u2033 \u2035 \u2103 \u2109 \uFE6A \uFF05 \uFFE0];
  79 $PO = [[:LineBreak =  Postfix_Numeric:] - $POX];
  80 $PRX = [\u00A4 \u00B1 \u20AC \u2116 \uFE69 \uFF04 \uFFE1 \uFFE5 \uFFE6];
  81 $PR = [[:LineBreak =  Prefix_Numeric:] - $PRX];
  82 $QU = [:LineBreak =  Quotation:];
  83 $RI = [:LineBreak =  Regional_Indicator:];
  84 $SA = [:LineBreak =  Complex_Context:];
  85 $SG = [:LineBreak =  Surrogate:];
  86 $SP = [:LineBreak =  Space:];
  87 $SY = [:LineBreak =  Break_Symbols:];
  88 $WJ = [:LineBreak =  Word_Joiner:];
  89 $XX = [:LineBreak =  Unknown:];
  90 $ZW = [:LineBreak =  ZWSpace:];
  91 $ZWJ = [:LineBreak = ZWJ:];
  92
  93 $EmojiNRK = [[\p{Emoji}] - [$RI \u002a\u00230-9©®™〰〽]];
  94 # Data for Extended Pictographic scraped from CLDR common/properties/ExtendedPictographic.txt, r13267
  95 $Extended_Pict = [\U0001F774-\U0001F77F\U00002700-\U00002701\U00002703-\U00002704\U0000270E\U00002710-\U00002711\U00002765-\U00002767\U0001F030-\U0001F093\U0001F094-\U0001F09F\U0001F10D-\U0001F10F\U0001F12F\U0001F16C-\U0001F16F\U0001F1AD-\U0001F1E5\U0001F260-\U0001F265\U0001F203-\U0001F20F\U0001F23C-\U0001F23F\U0001F249-\U0001F24F\U0001F252-\U0001F25F\U0001F266-\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\U00002605\U00002607-\U0000260D\U0000260F-\U00002610\U00002612\U00002616-\U00002617\U00002619-\U0000261C\U0000261E-\U0000261F\U00002621\U00002624-\U00002625\U00002627-\U00002629\U0000262B-\U0000262D\U00002630-\U00002637\U0000263B-\U00002647\U00002654-\U0000265F\U00002661-\U00002662\U00002664\U00002667\U00002669-\U0000267A\U0000267C-\U0000267E\U00002680-\U00002691\U00002695\U00002698\U0000269A\U0000269D-\U0000269F\U000026A2-\U000026A9\U000026AC-\U000026AF\U000026B2-\U000026BC\U000026BF-\U000026C3\U000026C6-\U000026C7\U000026C9-\U000026CD\U000026D0\U000026D2\U000026D5-\U000026E8\U000026EB-\U000026EF\U000026F6\U000026FB-\U000026FC\U000026FE-\U000026FF\U00002388\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-\U0001F90B\U0001F91F\U0001F928-\U0001F92F\U0001F931-\U0001F932\U0001F94C\U0001F95F-\U0001F96B\U0001F992-\U0001F997\U0001F9D0-\U0001F9E6\U0001F90C-\U0001F90F\U0001F93F\U0001F94D-\U0001F94F\U0001F96C-\U0001F97F\U0001F998-\U0001F9BF\U0001F9C1-\U0001F9CF\U0001F9E7-\U0001F9FF\U0001F6C6-\U0001F6CA\U0001F6D3-\U0001F6D4\U0001F6E6-\U0001F6E8\U0001F6EA\U0001F6F1-\U0001F6F2\U0001F6F7-\U0001F6F8\U0001F6D5-\U0001F6DF\U0001F6ED-\U0001F6EF\U0001F6F9-\U0001F6FF];
  96
  97 # By LB9, a ZWJ also behaves as a CM. Including it in the definition of CM avoids having to explicitly
  98 #         list it in the numerous rules that use CM.
  99 # By LB1, SA characters with general categor of Mn or Mc also resolve to CM.
 100
 101 $CM = [[:LineBreak = Combining_Mark:] $ZWJ [$SA & [[:Mn:][:Mc:]]]];
 102
 103 #   Dictionary character set, for triggering language-based break engines. Currently
 104 #   limited to LineBreak=Complex_Context (SA).
 105
 106 $dictionary = [$SA];
 107
 108 #
 109 #  Rule LB1.  By default, treat AI  (characters with ambiguous east Asian width),
 110 #                               SA  (Dictionary chars, excluding Mn and Mc)
 111 #                               SG  (Unpaired Surrogates)
 112 #                               XX  (Unknown, unassigned)
 113 #                         as $AL  (Alphabetic)
 114 #
 115 $ALPlus = [$AL $AI $SG $XX [$SA-[[:Mn:][:Mc:]]]];
 116
 117
 118 ## -------------------------------------------------
 119
 120 !!forward;
 121
 122 #
 123 # CAN_CM  is the set of characters that may combine with CM combining chars.
 124 #         Note that Linebreak UAX 14's concept of a combining char and the rules
 125 #         for what they can combine with are _very_ different from the rest of Unicode.
 126 #
 127 #         Note that $CM itself is left out of this set.  If CM is needed as a base
 128 #         it must be listed separately in the rule.
 129 #
 130 $CAN_CM  = [^$SP $BK $CR $LF $NL $ZW $CM];       # Bases that can   take CMs
 131 $CANT_CM = [ $SP $BK $CR $LF $NL $ZW $CM];       # Bases that can't take CMs
 132
 133 #
 134 # AL_FOLLOW  set of chars that can unconditionally follow an AL
 135 #            Needed in rules where stand-alone $CM s are treated as AL.
 136 #
 137 $AL_FOLLOW      = [$BK $CR $LF $NL $ZW $SP $CL $CP $EX $HL $IS $SY $WJ $GL $OP $QU $BA $HY $NS $IN $NU $PR $PO $POX $ALPlus];
 138
 139
 140 #
 141 #  Rule LB 4, 5    Mandatory (Hard) breaks.
 142 #
 143 $LB4Breaks    = [$BK $CR $LF $NL];
 144 $LB4NonBreaks = [^$BK $CR $LF $NL $CM];
 145 $CR $LF {100};
 146
 147 #
 148 #  LB 6    Do not break before hard line breaks.
 149 #
 150 $LB4NonBreaks?  $LB4Breaks {100};    # LB 5  do not break before hard breaks.
 151 $CAN_CM $CM*    $LB4Breaks {100};
 152 ^$CM+           $LB4Breaks {100};
 153
 154 # LB 7         x SP
 155 #              x ZW
 156 $LB4NonBreaks [$SP $ZW];
 157 $CAN_CM $CM*  [$SP $ZW];
 158 ^$CM+         [$SP $ZW];
 159
 160 #
 161 # LB 8         Break after zero width space
 162 #              TODO:  ZW SP* <break>
 163 #              An engine change is required to write the reverse rule for this.
 164 #              For now, leave the Unicode 5.2 rule, ZW <break>
 165 #
 166 $LB8Breaks    = [$LB4Breaks $ZW];
 167 $LB8NonBreaks = [[$LB4NonBreaks] - [$ZW]];
 168
 169 # LB 8a        ZWJ x (ID | Extended_Pict | EmojiNRK)   Emoji ZWJ sequences.
 170 #
 171 $ZWJ ($ID | $Extended_Pict | $EmojiNRK);
 172
 173 # LB 9     Combining marks.      X   $CM needs to behave like X, where X is not $SP, $BK $CR $LF $NL
 174 #                                $CM not covered by the above needs to behave like $AL
 175 #                                See definition of $CAN_CM.
 176
 177 $CAN_CM $CM+;                   #  Stick together any combining sequences that don't match other rules.
 178 ^$CM+;
 179
 180 #
 181 # LB 11  Do not break before or after WORD JOINER & related characters.
 182 #
 183 $CAN_CM $CM*  $WJ;
 184 $LB8NonBreaks $WJ;
 185 ^$CM+         $WJ;
 186
 187 $WJ $CM* .;
 188
 189 #
 190 # LB 12  Do not break after NBSP and related characters.
 191 #         GL  x
 192 #
 193 $GL $CM* .;
 194
 195 #
 196 # LB 12a  Do not break before NBSP and related characters ...
 197 #            [^SP BA HY] x GL
 198 #
 199 [[$LB8NonBreaks] - [$SP $BA $BAX $HY]] $CM* $GL;
 200 ^$CM+ $GL;
 201
 202
 203 #
 204 # LB 13   Don't break before ']' or '!' or ';' or '/', even after spaces.
 205 #
 206 # Do not include $EXX here
 207 $LB8NonBreaks $CL;
 208 $CAN_CM $CM*  $CL;
 209 ^$CM+         $CL;              # by rule 10, stand-alone CM behaves as AL
 210
 211 $LB8NonBreaks $CP;
 212 $CAN_CM $CM*  $CP;
 213 ^$CM+         $CP;              # by rule 10, stand-alone CM behaves as AL
 214
 215 $LB8NonBreaks $EX;
 216 $CAN_CM $CM*  $EX;
 217 ^$CM+         $EX;              # by rule 10, stand-alone CM behaves as AL
 218
 219 $LB8NonBreaks $IS;
 220 $CAN_CM $CM*  $IS;
 221 ^$CM+         $IS;              # by rule 10, stand-alone CM behaves as AL
 222
 223 $LB8NonBreaks $SY;
 224 $CAN_CM $CM*  $SY;
 225 ^$CM+         $SY;              # by rule 10, stand-alone CM behaves as AL
 226
 227
 228 #
 229 # LB 14  Do not break after OP, even after spaces
 230 #
 231 $OP $CM* $SP* .;
 232
 233 $OP $CM* $SP+ $CM+ $AL_FOLLOW?;    # by rule 10, stand-alone CM behaves as AL
 234                                    # by rule 8, CM following a SP is stand-alone.
 235
 236 # LB 15
 237 $QU $CM* $SP* $OP;
 238
 239 # LB 16
 240 # Do not break between closing punctuation and $NS, even with intervening spaces
 241 # But DO allow a break between closing punctuation and $NSX, don't include it here
 242 ($CL | $CP) $CM* $SP* $NS;
 243
 244 # LB 17
 245 $B2 $CM* $SP* $B2;
 246
 247 #
 248 # LB 18  Break after spaces.
 249 #
 250 $LB18NonBreaks = [$LB8NonBreaks - [$SP]];
 251 $LB18Breaks    = [$LB8Breaks $SP];
 252
 253
 254 # LB 19
 255 #         x QU
 256 $LB18NonBreaks $CM* $QU;
 257 ^$CM+               $QU;
 258
 259 #         QU  x
 260 $QU $CM* .;
 261
 262
 263 # LB 20
 264 #        <break>  $CB
 265 #        $CB   <break>
 266
 267 $LB20NonBreaks = [$LB18NonBreaks - $CB];
 268
 269 # LB 21        x   (BA | HY | NS)
 270 #           BB x
 271 #
 272 # DO allow breaks here before $BAX and $NSX, so don't include them
 273 $LB20NonBreaks $CM* ($BA | $HY | $NS);
 274 ^$CM+ ($BA | $HY | $NS);
 275
 276 $BB $CM* [^$CB];                                  #  $BB  x
 277 $BB $CM* $LB20NonBreaks;
 278
 279 # LB 21a Don't break after Hebrew + Hyphen
 280 #   HL (HY | BA) x
 281 #
 282 $HL $CM* ($HY | $BA | $BAX) $CM* [^$CB]?;
 283
 284 # LB 21b (forward) Don't break between SY and HL
 285 # (break between HL and SY already disallowed by LB 13 above)
 286 $SY $CM* $HL;
 287
 288 # LB 22
 289 ($ALPlus | $HL) $CM* $IN;
 290 ^$CM+    $IN;     #  by rule 10, any otherwise unattached CM behaves as AL
 291 $EX $CM*    $IN;
 292 ($ID | $EB | $EM) $CM*  $IN;
 293 # $IN $CM*    $IN;  # delete this rule for CSS loose
 294 $NU $CM*    $IN;
 295
 296
 297 # $LB 23
 298 #
 299 ($ALPlus | $HL) $CM* $NU;
 300 ^$CM+  $NU;       # Rule 10, any otherwise unattached CM behaves as AL
 301 $NU $CM* ($ALPlus | $HL);
 302
 303 # LB 23a
 304 # Do not include $POX here
 305 #
 306 $PR $CM* ($ID | $EB | $EM);
 307 ($ID | $EB | $EM) $CM*  $PO;
 308
 309
 310 #
 311 # LB 24
 312 #
 313 # Do not include $PRX here
 314 ($PR | $PO | $POX) $CM* ($ALPlus | $HL);
 315 ($ALPlus | $HL) $CM* ($PR | $PO | $POX);     # TODO: should this be ($PR | $PRX | $PO)
 316 ^$CM+ ($PR | $PO | $POX);       # Rule 10, any otherwise unattached CM behaves as AL
 317
 318 #
 319 # LB 25   Numbers.
 320 #
 321 # Here do not include $PRX at the beginning or $POX at the end
 322 (($PR | $PO | $POX) $CM*)? (($OP | $HY) $CM*)? $NU ($CM* ($NU | $SY | $IS))*
 323     ($CM* ($CL | $CP))? ($CM* ($PR | $PRX | $PO))?;
 324
 325 # LB 26  Do not break a Korean syllable
 326 #
 327 $JL $CM* ($JL | $JV | $H2 | $H3);
 328 ($JV | $H2) $CM* ($JV | $JT);
 329 ($JT | $H3) $CM* $JT;
 330
 331 # LB 27  Treat korean Syllable Block the same as ID  (don't break it)
 332 # Do not include $POX or $PRX here
 333 ($JL | $JV | $JT | $H2 | $H3) $CM* $IN;
 334 ($JL | $JV | $JT | $H2 | $H3) $CM* $PO;
 335 $PR $CM* ($JL | $JV | $JT | $H2 | $H3);
 336
 337
 338 # LB 28   Do not break between alphabetics
 339 #
 340 ($ALPlus | $HL) $CM* ($ALPlus | $HL);
 341 ^$CM+ ($ALPlus | $HL);      # The $CM+ is from rule 10, an unattached CM is treated as AL
 342
 343 # LB 29
 344 $IS $CM* ($ALPlus | $HL);
 345
 346 # LB 30
 347 ($ALPlus | $HL | $NU) $CM* $OP;
 348 ^$CM+ $OP;         # The $CM+ is from rule 10, an unattached CM is treated as AL.
 349 $CP $CM* ($ALPlus | $HL | $NU);
 350
 351 # LB 30a  Do not break between regional indicators. Break after pairs of them.
 352 #         Tricky interaction with LB8a: ZWJ x ID
 353 $RI $CM* $RI                / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM] {eof}];
 354 $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}];
 355 $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}];
 356
 357 $RI $CM* $RI $CM* [$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS {eof}];
 358 $RI $CM* $RI $CM* $ZWJ ($ID | $Extended_Pict | $EmojiNRK);
 359
 360 # LB 30b Do not break between an Emoji Base and an Emoji Modifier
 361 $EB $CM* $EM;
 362
 363 #
 364 #  Reverse Rules.
 365 #
 366 ## -------------------------------------------------
 367
 368 !!reverse;
 369
 370 #  LB 9 Combining Marks.
 371 #  Stick together any combining sequences that don't match other rules.
 372
 373 ^$CM+ $CAN_CM?;
 374
 375 #
 376 #  Sequences of the form  (shown forwards)
 377 #      [CANT_CM]  <break>  [CM]  [whatever]
 378 #  The CM needs to behave as an AL
 379 #
 380 $AL_FOLLOW $CM+ / (
 381           [$BK $CR $LF $NL $ZW {eof}] |
 382           $SP+ $CM+ $SP |
 383           $SP+ $CM* ([^$OP $CM $SP] | [$AL {eof}]));   # if LB 14 will match, need to surpress this break.
 384                                                #  LB14 says    OP SP* x .
 385                                                #    becomes    OP SP* x AL
 386                                                #    becomes    OP SP* x CM+ AL_FOLLOW
 387                                                #
 388                                                # Further note:  the $AL in [$AL {eof}] is only to work around
 389                                                #                a rule compiler bug which complains about
 390                                                #                empty sets otherwise.
 391
 392
 393 # LB 4, 5, 6
 394
 395 $LB4Breaks [$LB4NonBreaks-$CM];
 396 $LB4Breaks $CM+ $CAN_CM;
 397 $LF $CR;
 398
 399
 400 # LB 7         x SP
 401 #              x ZW
 402 [$SP $ZW] [$LB4NonBreaks-$CM];
 403 [$SP $ZW] $CM+ $CAN_CM;
 404
 405 # LB 8 ZW SP* <break>
 406 #     TODO: to implement this, we need more than one look-ahead hard break in play at a time.
 407 #           Requires an engine enhancement.
 408 #   / $SP* $ZW
 409
 410 # LB 8a        ZWJ x (ID | Extended_Pict | EmojiNRK)
 411 #
 412 ($ID | $Extended_Pict | $EmojiNRK) $ZWJ $CM* $CAN_CM?;
 413
 414
 415 # LB 9,10  Combining marks.
 416 #    X   $CM needs to behave like X, where X is not $SP or controls.
 417 #    $CM not covered by the above needs to behave like $AL
 418 # Stick together any combining sequences that don't match other rules.
 419 ^$CM+ $CAN_CM;
 420
 421
 422 # LB 11
 423 #
 424 $WJ $CM* $CAN_CM;
 425 $WJ      [$LB8NonBreaks-$CM];
 426
 427      $CANT_CM $CM* $WJ;
 428 $CAN_CM  $CM* $WJ;
 429
 430 # LB 12a
 431 #      [^SP BA HY] x GL
 432 #
 433 $GL $CM* [$LB8NonBreaks-[$CM $SP $BA $BAX $HY]];
 434
 435 # LB 12
 436 #     GL  x
 437 #
 438 $CANT_CM $CM* $GL;
 439 $CAN_CM $CM* $GL;
 440
 441
 442 # LB 13
 443 # Do not include $EXX here
 444 $CL $CM+ $CAN_CM;
 445 $CP $CM+ $CAN_CM;
 446 $EX $CM+ $CAN_CM;
 447 $IS $CM+ $CAN_CM;
 448 $SY $CM+ $CAN_CM;
 449
 450 $CL [$LB8NonBreaks-$CM];
 451 $CP [$LB8NonBreaks-$CM];
 452 $EX [$LB8NonBreaks-$CM];
 453 $IS [$LB8NonBreaks-$CM];
 454 $SY [$LB8NonBreaks-$CM];
 455
 456
 457 # LB 14    OP SP* x
 458 #
 459 .   $SP* $CM* $OP;
 460 $AL_FOLLOW? $CM+ $SP+ $CM* $OP;     #  by LB 10, behaves like $AL_FOLLOW? $AL $SP+ $CM* $OP
 461
 462
 463 # LB 15
 464 $OP $SP* $CM* $QU;
 465
 466 # LB 16
 467 # Don't include $NSX here
 468 $NS $SP* $CM* ($CL | $CP);
 469
 470 # LB 17
 471 $B2 $SP* $CM* $B2;
 472
 473 # LB 18  break after spaces
 474 #        Nothing explicit needed here.
 475
 476
 477 #
 478 # LB 19
 479 #
 480 $QU $CM* $CAN_CM;                                #   . x QU
 481 $QU      $LB18NonBreaks;
 482
 483
 484 $CAN_CM  $CM* $QU;                               #   QU x .
 485      $CANT_CM $CM* $QU;
 486
 487 #
 488 #  LB 20  Break before and after CB.
 489 #         nothing needed here.
 490 #
 491
 492 # LB 21
 493 # Don't include $BAX or $NSX here
 494 ($BA | $HY | $NS) $CM* [$LB20NonBreaks-$CM];     #  . x (BA | HY | NS)
 495
 496 [$LB20NonBreaks-$CM] $CM* $BB;                   #  BB x .
 497 [^$CB] $CM* $BB;                                      #
 498
 499 # LB21a
 500 [^$CM $CB]? $CM* ($HY | $BA | $BAX) $CM* $HL;
 501
 502 # LB21b (reverse)
 503 $HL $CM* $SY;
 504
 505 # LB 22
 506 $IN $CM* ($ALPlus | $HL);
 507 $IN $CM* $EX;
 508 $IN $CM* ($ID | $EB | $EM);
 509 # $IN $CM* $IN; # delete this rule for CSS loose
 510 $IN $CM* $NU;
 511
 512 # LB 23
 513 # Do not include $POX here
 514 $NU $CM* ($ALPlus | $HL);
 515 ($ALPlus | $HL) $CM* $NU;
 516
 517 # LB23a
 518 # Do not include $PRX here
 519 ($ID | $EB | $EM) $CM* $PR;
 520 $PO $CM* ($ID | $EB | $EM);
 521
 522 # LB 24
 523 # Do not include $PRX here
 524 ($ALPlus | $HL) $CM* ($PR | $PO | $POX);
 525 ($PR | $PO | $POX) $CM* ($ALPlus | $HL);
 526
 527
 528 # LB 25
 529 # Here do not include $POX at the beginning or $PRX at the end
 530 ($CM* ($PR | $PRX | $PO))? ($CM* ($CL | $CP))? ($CM* ($NU | $IS | $SY))* $CM* $NU ($CM* ($OP | $HY))? ($CM* ($PR | $PO | $POX))?;
 531
 532 # LB 26
 533 ($H3 | $H2 | $JV | $JL) $CM* $JL;
 534 ($JT | $JV) $CM* ($H2 | $JV);
 535 $JT $CM* ($H3 | $JT);
 536
 537 # LB 27
 538 # Do not include $POX or $PRX here
 539 $IN $CM* ($H3 | $H2 | $JT | $JV | $JL);
 540 $PO $CM* ($H3 | $H2 | $JT | $JV | $JL);
 541  ($H3 | $H2 | $JT | $JV | $JL) $CM* $PR;
 542
 543 # LB 28
 544 ($ALPlus | $HL) $CM* ($ALPlus | $HL);
 545
 546
 547 # LB 29
 548 ($ALPlus | $HL) $CM* $IS;
 549
 550 # LB 30
 551 $OP $CM* ($ALPlus | $HL | $NU);
 552 ($ALPlus | $HL | $NU) $CM* $CP;
 553
 554 # LB 30a
 555 #    Pairs of Regional Indicators.
 556 #    The following two rules are nearly identical. The first matches only sequences with an odd number of adjacent RIs,
 557 #    the second with an even number. Stripping away the cruft they look like
 558 #         [^RI] RI / (RI RI)+ ^RI;
 559 #         [^RI] RI RI / (RI RI)+ ^RI;
 560 #
 561 # Line Loose tailoring: Don't include NSX here.
 562 [{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]];
 563 [{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]];
 564
 565 # In general, adjacent RIs stay together. The hard-break rules, above, overide this, forcing in the boundaries between pairs.
 566 $RI $CM* $RI;
 567
 568 #    WJ, GL, QU, etc. are classes with rules like "WJ x "   which includes "WJ x RI".
 569 $RI $CM* ([$WJ $GL $QU $BB] |  (($HY | $BA)$CM* $HL));
 570
 571
 572 # LB 30b Do not break between an Emoji Base and an Emoji Modifier
 573 $EM $CM* $EB;
 574
 575
 576 ## -------------------------------------------------
 577
 578 !!safe_reverse;
 579
 580 # LB 9
 581 ^$CM+ [^$CM $BK $CR $LF $NL $ZW $SP];
 582 ^$CM+ $SP / .;
 583
 584 # LB 14
 585 $SP+ $CM* $OP;
 586
 587 # LB 15
 588 $SP+ $CM* $QU;
 589
 590 # LB 16
 591 $SP+ $CM* ($CL | $CP);
 592
 593 # LB 17
 594 $SP+ $CM* $B2;
 595
 596 # LB 21
 597 $CM* ($HY | $BA | $BAX) $CM* $HL;
 598
 599 # LB 25
 600 ($CM* ($IS | $SY))+ $CM* $NU;
 601 ($CL | $CP) $CM* ($NU | $IS | $SY);
 602
 603 #  LB 30
 604 ($CM* $RI)+;
 605
 606 # For dictionary-based break
 607 $dictionary $dictionary;
 608
 609 ## -------------------------------------------------
 610
 611 !!safe_forward;
 612
 613 # Skip forward over all character classes that are involved in
 614 #   rules containing patterns with possibly more than one char
 615 #   of context.
 616 #
 617 #  It might be slightly more efficient to have specific rules
 618 #  instead of one generic one, but only if we could
 619 #  turn off rule chaining.  We don't want to move more
 620 #  than necessary.
 621 #
 622 ^[$CM $OP $QU $CL $CP $B2 $PR $PRX $HY $BA $BAX $SP $RI $ZWJ $dictionary]+ [^$CM $OP $QU $CL $CP $B2 $PR $PRX $HY $BA $BAX $RI $ZWJ $dictionary];
 623 $dictionary $dictionary;
 624