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_fi.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# tailored as noted in 2nd paragraph below. 13# 14# Includes extensions to the handling of emoji ZWJ sequences from 15# https://goo.gl/cluFCn 16# 17# TODO: Rule LB 8 remains as it was in Unicode 5.2 18# This is only because of a limitation of ICU break engine implementation, 19# not because the older behavior is desirable. 20# 21# This tailors the line break behavior for Finnish, while otherwise behaving 22# per UAX 14 which corresponds to CSS line-break=strict (BCP47 -u-lb-strict). 23# It sets characters of class CJ to behave like NS. 24# 25# This corresponds to CSS line-break=strict (BCP47 -u-lb-strict). 26# It sets characters of class CJ to behave like NS. 27 28# 29# Character Classes defined by TR 14. 30# 31 32!!chain; 33 34$AI = [:LineBreak = Ambiguous:]; 35$AL = [:LineBreak = Alphabetic:]; 36$BA = [:LineBreak = Break_After:]; 37$HH = [\u2010]; # \u2010 is HYPHEN, default line break is BA. 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$H3 = [:LineBreak = H3:]; 55$ID = [:LineBreak = Ideographic:]; 56$IN = [:LineBreak = Inseperable:]; 57$IS = [:LineBreak = Infix_Numeric:]; 58$JL = [:LineBreak = JL:]; 59$JV = [:LineBreak = JV:]; 60$JT = [:LineBreak = JT:]; 61$LF = [:LineBreak = Line_Feed:]; 62$NL = [:LineBreak = Next_Line:]; 63# NS includes CJ for CSS strict line breaking. 64$NS = [[:LineBreak = Nonstarter:] $CJ]; 65$NU = [:LineBreak = Numeric:]; 66$OP = [:LineBreak = Open_Punctuation:]; 67$PO = [:LineBreak = Postfix_Numeric:]; 68$PR = [:LineBreak = Prefix_Numeric:]; 69$QU = [:LineBreak = Quotation:]; 70$RI = [:LineBreak = Regional_Indicator:]; 71$SA = [:LineBreak = Complex_Context:]; 72$SG = [:LineBreak = Surrogate:]; 73$SP = [:LineBreak = Space:]; 74$SY = [:LineBreak = Break_Symbols:]; 75$WJ = [:LineBreak = Word_Joiner:]; 76$XX = [:LineBreak = Unknown:]; 77$ZW = [:LineBreak = ZWSpace:]; 78$ZWJ = [:LineBreak = ZWJ:]; 79 80$EmojiNRK = [[\p{Emoji}] - [$RI \u002a\u00230-9©®™〰〽]]; 81# Data for Extended Pictographic scraped from CLDR common/properties/ExtendedPictographic.txt, r12773 82$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]; 83 84# By LB9, a ZWJ also behaves as a CM. Including it in the definition of CM avoids having to explicitly 85# list it in the numerous rules that use CM. 86# By LB1, SA characters with general categor of Mn or Mc also resolve to CM. 87 88$CM = [[:LineBreak = Combining_Mark:] $ZWJ [$SA & [[:Mn:][:Mc:]]]]; 89 90# Dictionary character set, for triggering language-based break engines. Currently 91# limited to LineBreak=Complex_Context (SA). 92 93$dictionary = [$SA]; 94 95# 96# Rule LB1. By default, treat AI (characters with ambiguous east Asian width), 97# SA (Dictionary chars, excluding Mn and Mc) 98# SG (Unpaired Surrogates) 99# XX (Unknown, unassigned) 100# as $AL (Alphabetic) 101# 102$ALPlus = [$AL $AI $SG $XX [$SA-[[:Mn:][:Mc:]]]]; 103 104 105## ------------------------------------------------- 106 107!!forward; 108 109# 110# CAN_CM is the set of characters that may combine with CM combining chars. 111# Note that Linebreak UAX 14's concept of a combining char and the rules 112# for what they can combine with are _very_ different from the rest of Unicode. 113# 114# Note that $CM itself is left out of this set. If CM is needed as a base 115# it must be listed separately in the rule. 116# 117$CAN_CM = [^$SP $BK $CR $LF $NL $ZW $CM]; # Bases that can take CMs 118$CANT_CM = [ $SP $BK $CR $LF $NL $ZW $CM]; # Bases that can't take CMs 119 120# 121# AL_FOLLOW set of chars that can unconditionally follow an AL 122# Needed in rules where stand-alone $CM s are treated as AL. 123# 124$AL_FOLLOW = [$BK $CR $LF $NL $ZW $SP $CL $CP $EX $HL $IS $SY $WJ $GL $OP $QU $BA $HH $HY $NS $IN $NU $PR $PO $ALPlus]; 125 126 127# 128# Rule LB 4, 5 Mandatory (Hard) breaks. 129# 130$LB4Breaks = [$BK $CR $LF $NL]; 131$LB4NonBreaks = [^$BK $CR $LF $NL $CM]; 132$CR $LF {100}; 133 134# 135# LB 6 Do not break before hard line breaks. 136# 137$LB4NonBreaks? $LB4Breaks {100}; # LB 5 do not break before hard breaks. 138$CAN_CM $CM* $LB4Breaks {100}; 139^$CM+ $LB4Breaks {100}; 140 141# LB 7 x SP 142# x ZW 143$LB4NonBreaks [$SP $ZW]; 144$CAN_CM $CM* [$SP $ZW]; 145^$CM+ [$SP $ZW]; 146 147# 148# LB 8 Break after zero width space 149# TODO: ZW SP* <break> 150# An engine change is required to write the reverse rule for this. 151# For now, leave the Unicode 5.2 rule, ZW <break> 152# 153$LB8Breaks = [$LB4Breaks $ZW]; 154$LB8NonBreaks = [[$LB4NonBreaks] - [$ZW]]; 155 156# LB 8a ZWJ x (ID | Extended_Pict | EmojiNRK) Emoji ZWJ sequences. 157# 158$ZWJ ($ID | $Extended_Pict | $EmojiNRK); 159 160# LB 9 Combining marks. X $CM needs to behave like X, where X is not $SP, $BK $CR $LF $NL 161# $CM not covered by the above needs to behave like $AL 162# See definition of $CAN_CM. 163 164$CAN_CM $CM+; # Stick together any combining sequences that don't match other rules. 165^$CM+; 166 167# 168# LB 11 Do not break before or after WORD JOINER & related characters. 169# 170$CAN_CM $CM* $WJ; 171$LB8NonBreaks $WJ; 172^$CM+ $WJ; 173 174$WJ $CM* .; 175 176# 177# LB 12 Do not break after NBSP and related characters. 178# GL x 179# 180$GL $CM* .; 181 182# 183# LB 12a Do not break before NBSP and related characters ... 184# [^SP BA HY] x GL 185# 186[[$LB8NonBreaks] - [$SP $BA $HH $HY]] $CM* $GL; 187^$CM+ $GL; 188 189 190 191# 192# LB 13 Don't break before ']' or '!' or ';' or '/', even after spaces. 193# 194$LB8NonBreaks $CL; 195$CAN_CM $CM* $CL; 196^$CM+ $CL; # by rule 10, stand-alone CM behaves as AL 197 198$LB8NonBreaks $CP; 199$CAN_CM $CM* $CP; 200^$CM+ $CP; # by rule 10, stand-alone CM behaves as AL 201 202$LB8NonBreaks $EX; 203$CAN_CM $CM* $EX; 204^$CM+ $EX; # by rule 10, stand-alone CM behaves as AL 205 206$LB8NonBreaks $IS; 207$CAN_CM $CM* $IS; 208^$CM+ $IS; # by rule 10, stand-alone CM behaves as AL 209 210$LB8NonBreaks $SY; 211$CAN_CM $CM* $SY; 212^$CM+ $SY; # by rule 10, stand-alone CM behaves as AL 213 214 215# 216# LB 14 Do not break after OP, even after spaces 217# 218$OP $CM* $SP* .; 219 220$OP $CM* $SP+ $CM+ $AL_FOLLOW?; # by rule 10, stand-alone CM behaves as AL 221 # by rule 8, CM following a SP is stand-alone. 222 223# LB 15 224$QU $CM* $SP* $OP; 225 226# LB 16 227($CL | $CP) $CM* $SP* $NS; 228 229# LB 17 230$B2 $CM* $SP* $B2; 231 232# 233# LB 18 Break after spaces. 234# 235$LB18NonBreaks = [$LB8NonBreaks - [$SP]]; 236$LB18Breaks = [$LB8Breaks $SP]; 237 238 239# LB 19 240# x QU 241$LB18NonBreaks $CM* $QU; 242^$CM+ $QU; 243 244# QU x 245$QU $CM* .; 246 247 248# LB 20 249# <break> $CB 250# $CB <break> 251 252$LB20NonBreaks = [$LB18NonBreaks - $CB]; 253 254# LB 20.09 added rule for Finnish tailoring 255# LB 21 x (BA | HY | NS) 256# BB x 257# 258$LB20NonBreaks $CM* ($BA | $HH | $HY | $NS) $CM* / $AL; 259$LB20NonBreaks $CM* ($BA | $HH | $HY | $NS); 260($HY | $HH) $AL; 261^$CM+ ($BA | $HY | $HH | $NS); 262 263$BB $CM* [^$CB]; # $BB x 264$BB $CM* $LB20NonBreaks; 265 266# LB 21a Don't break after Hebrew + Hyphen 267# HL (HY | BA) x 268# 269$HL $CM* ($HY | $BA | $HH) $CM* [^$CB]?; 270 271# LB 21b (forward) Don't break between SY and HL 272# (break between HL and SY already disallowed by LB 13 above) 273$SY $CM* $HL; 274 275# LB 22 276($ALPlus | $HL) $CM* $IN; 277^$CM+ $IN; # by rule 10, any otherwise unattached CM behaves as AL 278$EX $CM* $IN; 279($ID | $EB | $EM) $CM* $IN; 280$IN $CM* $IN; 281$NU $CM* $IN; 282 283 284# $LB 23 285# 286($ALPlus | $HL) $CM* $NU; 287^$CM+ $NU; # Rule 10, any otherwise unattached CM behaves as AL 288$NU $CM* ($ALPlus | $HL); 289 290# LB 23a 291# 292$PR $CM* ($ID | $EB | $EM); 293($ID | $EB | $EM) $CM* $PO; 294 295 296# 297# LB 24 298# 299($PR | $PO) $CM* ($ALPlus | $HL); 300($ALPlus | $HL) $CM* ($PR | $PO); 301^$CM+ ($PR | $PO); # Rule 10, any otherwise unattached CM behaves as AL 302 303# 304# LB 25 Numbers. 305# 306(($PR | $PO) $CM*)? (($OP | $HY) $CM*)? $NU ($CM* ($NU | $SY | $IS))* 307 ($CM* ($CL | $CP))? ($CM* ($PR | $PO))?; 308 309# LB 26 Do not break a Korean syllable 310# 311$JL $CM* ($JL | $JV | $H2 | $H3); 312($JV | $H2) $CM* ($JV | $JT); 313($JT | $H3) $CM* $JT; 314 315# LB 27 Treat korean Syllable Block the same as ID (don't break it) 316($JL | $JV | $JT | $H2 | $H3) $CM* $IN; 317($JL | $JV | $JT | $H2 | $H3) $CM* $PO; 318$PR $CM* ($JL | $JV | $JT | $H2 | $H3); 319 320 321# LB 28 Do not break between alphabetics 322# 323($ALPlus | $HL) $CM* ($ALPlus | $HL); 324^$CM+ ($ALPlus | $HL); # The $CM+ is from rule 10, an unattached CM is treated as AL 325 326# LB 29 327$IS $CM* ($ALPlus | $HL); 328 329# LB 30 330($ALPlus | $HL | $NU) $CM* $OP; 331^$CM+ $OP; # The $CM+ is from rule 10, an unattached CM is treated as AL. 332$CP $CM* ($ALPlus | $HL | $NU); 333 334# LB 30a Do not break between regional indicators. Break after pairs of them. 335# Tricky interaction with LB8a: ZWJ x ID 336$RI $CM* $RI / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM] {eof}]; 337$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 $EmojiNRK] {eof}]; 338$RI $CM* $RI $CM* [$CM-$ZWJ] / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $CM] {eof}]; 339 340$RI $CM* $RI $CM* [$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS {eof}]; 341$RI $CM* $RI $CM* $ZWJ ($ID | $Extended_Pict | $EmojiNRK); 342 343# LB 30b Do not break between an Emoji Base and an Emoji Modifier 344$EB $CM* $EM; 345 346# 347# Reverse Rules. 348# 349## ------------------------------------------------- 350 351!!reverse; 352 353# LB 9 Combining Marks. 354# Stick together any combining sequences that don't match other rules. 355 356^$CM+ $CAN_CM?; 357 358# 359# Sequences of the form (shown forwards) 360# [CANT_CM] <break> [CM] [whatever] 361# The CM needs to behave as an AL 362# 363$AL_FOLLOW $CM+ / ( 364 [$BK $CR $LF $NL $ZW {eof}] | 365 $SP+ $CM+ $SP | 366 $SP+ $CM* ([^$OP $CM $SP] | [$AL {eof}])); # if LB 14 will match, need to surpress this break. 367 # LB14 says OP SP* x . 368 # becomes OP SP* x AL 369 # becomes OP SP* x CM+ AL_FOLLOW 370 # 371 # Further note: the $AL in [$AL {eof}] is only to work around 372 # a rule compiler bug which complains about 373 # empty sets otherwise. 374 375 376# LB 4, 5, 6 377 378$LB4Breaks [$LB4NonBreaks-$CM]; 379$LB4Breaks $CM+ $CAN_CM; 380$LF $CR; 381 382 383# LB 7 x SP 384# x ZW 385[$SP $ZW] [$LB4NonBreaks-$CM]; 386[$SP $ZW] $CM+ $CAN_CM; 387 388# LB 8 ZW SP* <break> 389# TODO: to implement this, we need more than one look-ahead hard break in play at a time. 390# Requires an engine enhancement. 391# / $SP* $ZW 392 393# LB 8a ZWJ x (ID | Extended_Pict | EmojiNRK) 394# 395($ID | $Extended_Pict | $EmojiNRK) $ZWJ $CM* $CAN_CM?; 396 397 398# LB 9,10 Combining marks. 399# X $CM needs to behave like X, where X is not $SP or controls. 400# $CM not covered by the above needs to behave like $AL 401# Stick together any combining sequences that don't match other rules. 402^$CM+ $CAN_CM; 403 404 405# LB 11 406# 407$WJ $CM* $CAN_CM; 408$WJ [$LB8NonBreaks-$CM]; 409 410 $CANT_CM $CM* $WJ; 411$CAN_CM $CM* $WJ; 412 413# LB 12a 414# [^SP BA HY] x GL 415# 416$GL $CM* [$LB8NonBreaks-[$CM $SP $BA $HH $HY]]; 417 418# LB 12 419# GL x 420# 421$CANT_CM $CM* $GL; 422$CAN_CM $CM* $GL; 423 424 425# LB 13 426$CL $CM+ $CAN_CM; 427$CP $CM+ $CAN_CM; 428$EX $CM+ $CAN_CM; 429$IS $CM+ $CAN_CM; 430$SY $CM+ $CAN_CM; 431 432$CL [$LB8NonBreaks-$CM]; 433$CP [$LB8NonBreaks-$CM]; 434$EX [$LB8NonBreaks-$CM]; 435$IS [$LB8NonBreaks-$CM]; 436$SY [$LB8NonBreaks-$CM]; 437 438 439# LB 14 OP SP* x 440# 441. $SP* $CM* $OP; 442$AL_FOLLOW? $CM+ $SP+ $CM* $OP; # by LB 10, behaves like $AL_FOLLOW? $AL $SP+ $CM* $OP 443 444 445# LB 15 446$OP $SP* $CM* $QU; 447 448# LB 16 449$NS $SP* $CM* ($CL | $CP); 450 451# LB 17 452$B2 $SP* $CM* $B2; 453 454# LB 18 break after spaces 455# Nothing explicit needed here. 456 457 458# 459# LB 19 460# 461$QU $CM* $CAN_CM; # . x QU 462$QU $LB18NonBreaks; 463 464 465$CAN_CM $CM* $QU; # QU x . 466 $CANT_CM $CM* $QU; 467 468# 469# LB 20 Break before and after CB. 470# nothing needed here. 471# 472 473# LB 20.09 added rule for Finnish tailoring 474$AL ($HY | $HH) / $SP; 475 476# LB 21 477($BA | $HH | $HY | $NS) $CM* [$LB20NonBreaks-$CM]; # . x (BA | HY | NS) 478 479[$LB20NonBreaks-$CM] $CM* $BB; # BB x . 480[^$CB] $CM* $BB; # 481 482# LB21a 483[^$CB] $CM* ($HY | $BA | $HH) $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 | $HH) $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 $SP $RI $ZWJ $dictionary]+ [^$CM $OP $QU $CL $CP $B2 $PR $HY $BA $RI $ZWJ $dictionary]; 600$dictionary $dictionary; 601 602