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Diffstat (limited to 'intl/icu/source/data/brkitr/rules/line.txt')
| -rw-r--r-- | intl/icu/source/data/brkitr/rules/line.txt | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/intl/icu/source/data/brkitr/rules/line.txt b/intl/icu/source/data/brkitr/rules/line.txt new file mode 100644 index 0000000000..3062a9854f --- /dev/null +++ b/intl/icu/source/data/brkitr/rules/line.txt @@ -0,0 +1,364 @@ +# Copyright (C) 2016 and later: Unicode, Inc. and others. +# License & terms of use: http://www.unicode.org/copyright.html +# Copyright (c) 2002-2016 International Business Machines Corporation and +# others. All Rights Reserved. +# +# file: line.txt +# +# Line Breaking Rules +# Implement default line breaking as defined by +# Unicode Standard Annex #14 (https://www.unicode.org/reports/tr14/) +# for Unicode 14.0, with the following modification: +# +# Boundaries between hyphens and following letters are suppressed when +# there is a boundary preceding the hyphen. See rule 20.9 +# +# This corresponds to CSS line-break=strict (BCP47 -u-lb-strict). +# It sets characters of class CJ to behave like NS. + +# +# Character Classes defined by TR 14. +# + +!!chain; +!!quoted_literals_only; + +$AI = [:LineBreak = Ambiguous:]; +$AL = [:LineBreak = Alphabetic:]; +$BA = [:LineBreak = Break_After:]; +$HH = [\u2010]; # \u2010 is HYPHEN, default line break is BA. +$BB = [:LineBreak = Break_Before:]; +$BK = [:LineBreak = Mandatory_Break:]; +$B2 = [:LineBreak = Break_Both:]; +$CB = [:LineBreak = Contingent_Break:]; +$CJ = [:LineBreak = Conditional_Japanese_Starter:]; +$CL = [:LineBreak = Close_Punctuation:]; +# $CM = [:LineBreak = Combining_Mark:]; +$CP = [:LineBreak = Close_Parenthesis:]; +$CR = [:LineBreak = Carriage_Return:]; +$EB = [:LineBreak = EB:]; +$EM = [:LineBreak = EM:]; +$EX = [:LineBreak = Exclamation:]; +$GL = [:LineBreak = Glue:]; +$HL = [:LineBreak = Hebrew_Letter:]; +$HY = [:LineBreak = Hyphen:]; +$H2 = [:LineBreak = H2:]; +$H3 = [:LineBreak = H3:]; +$ID = [:LineBreak = Ideographic:]; +$IN = [:LineBreak = Inseperable:]; +$IS = [:LineBreak = Infix_Numeric:]; +$JL = [:LineBreak = JL:]; +$JV = [:LineBreak = JV:]; +$JT = [:LineBreak = JT:]; +$LF = [:LineBreak = Line_Feed:]; +$NL = [:LineBreak = Next_Line:]; +# NS includes CJ for CSS strict line breaking. +$NS = [[:LineBreak = Nonstarter:] $CJ]; +$NU = [:LineBreak = Numeric:]; +$OP = [:LineBreak = Open_Punctuation:]; +$PO = [:LineBreak = Postfix_Numeric:]; +$PR = [:LineBreak = Prefix_Numeric:]; +$QU = [:LineBreak = Quotation:]; +$RI = [:LineBreak = Regional_Indicator:]; +$SA = [:LineBreak = Complex_Context:]; +$SG = [:LineBreak = Surrogate:]; +$SP = [:LineBreak = Space:]; +$SY = [:LineBreak = Break_Symbols:]; +$WJ = [:LineBreak = Word_Joiner:]; +$XX = [:LineBreak = Unknown:]; +$ZW = [:LineBreak = ZWSpace:]; +$ZWJ = [:LineBreak = ZWJ:]; + +# OP30 and CP30 are variants of OP and CP that appear in-line in rule LB30 from UAX 14, +# without a formal name. Because ICU rules require multiple uses of the expressions, +# give them a single definition with a name + +$OP30 = [$OP - [\p{ea=F}\p{ea=W}\p{ea=H}]]; +$CP30 = [$CP - [\p{ea=F}\p{ea=W}\p{ea=H}]]; + +$ExtPictUnassigned = [\p{Extended_Pictographic} & \p{Cn}]; + +# By LB9, a ZWJ also behaves as a CM. Including it in the definition of CM avoids having to explicitly +# list it in the numerous rules that use CM. +# By LB1, SA characters with general categor of Mn or Mc also resolve to CM. + +$CM = [[:LineBreak = Combining_Mark:] $ZWJ [$SA & [[:Mn:][:Mc:]]]]; +$CMX = [[$CM] - [$ZWJ]]; + +# Dictionary character set, for triggering language-based break engines. Currently +# limited to LineBreak=Complex_Context (SA). + +$dictionary = [$SA]; + +# +# Rule LB1. By default, treat AI (characters with ambiguous east Asian width), +# SA (Dictionary chars, excluding Mn and Mc) +# SG (Unpaired Surrogates) +# XX (Unknown, unassigned) +# as $AL (Alphabetic) +# +$ALPlus = [$AL $AI $SG $XX [$SA-[[:Mn:][:Mc:]]]]; + + +## ------------------------------------------------- + +# +# CAN_CM is the set of characters that may combine with CM combining chars. +# Note that Linebreak UAX 14's concept of a combining char and the rules +# for what they can combine with are _very_ different from the rest of Unicode. +# +# Note that $CM itself is left out of this set. If CM is needed as a base +# it must be listed separately in the rule. +# +$CAN_CM = [^$SP $BK $CR $LF $NL $ZW $CM]; # Bases that can take CMs +$CANT_CM = [ $SP $BK $CR $LF $NL $ZW $CM]; # Bases that can't take CMs + +# +# AL_FOLLOW set of chars that can unconditionally follow an AL +# Needed in rules where stand-alone $CM s are treated as AL. +# +$AL_FOLLOW = [$BK $CR $LF $NL $ZW $SP $CL $CP $EX $HL $IS $SY $WJ $GL $OP30 $QU $BA $HY $NS $IN $NU $PR $PO $ALPlus]; + + +# +# Rule LB 4, 5 Mandatory (Hard) breaks. +# +$LB4Breaks = [$BK $CR $LF $NL]; +$LB4NonBreaks = [^$BK $CR $LF $NL $CM]; +$CR $LF {100}; + +# +# LB 6 Do not break before hard line breaks. +# +$LB4NonBreaks? $LB4Breaks {100}; # LB 5 do not break before hard breaks. +$CAN_CM $CM* $LB4Breaks {100}; +^$CM+ $LB4Breaks {100}; + +# LB 7 x SP +# x ZW +$LB4NonBreaks [$SP $ZW]; +$CAN_CM $CM* [$SP $ZW]; +^$CM+ [$SP $ZW]; + +# +# LB 8 Break after zero width space +# ZW SP* รท +# +$LB8Breaks = [$LB4Breaks $ZW]; +$LB8NonBreaks = [[$LB4NonBreaks] - [$ZW]]; +$ZW $SP* / [^$SP $ZW $LB4Breaks]; + +# LB 8a ZWJ x Do not break Emoji ZWJ sequences. +# +$ZWJ [^$CM]; + +# LB 9 Combining marks. X $CM needs to behave like X, where X is not $SP, $BK $CR $LF $NL +# $CM not covered by the above needs to behave like $AL +# See definition of $CAN_CM. + +$CAN_CM $CM+; # Stick together any combining sequences that don't match other rules. +^$CM+; + +# +# LB 11 Do not break before or after WORD JOINER & related characters. +# +$CAN_CM $CM* $WJ; +$LB8NonBreaks $WJ; +^$CM+ $WJ; + +$WJ $CM* .; + +# +# LB 12 Do not break after NBSP and related characters. +# GL x +# +$GL $CM* .; + +# +# LB 12a Do not break before NBSP and related characters ... +# [^SP BA HY] x GL +# +[[$LB8NonBreaks] - [$SP $BA $HY]] $CM* $GL; +^$CM+ $GL; + + + + +# LB 13 Don't break before ']' or '!' or '/', even after spaces. +# +$LB8NonBreaks $CL; +$CAN_CM $CM* $CL; +^$CM+ $CL; # by rule 10, stand-alone CM behaves as AL + +$LB8NonBreaks $CP; +$CAN_CM $CM* $CP; +^$CM+ $CP; # by rule 10, stand-alone CM behaves as AL + +$LB8NonBreaks $EX; +$CAN_CM $CM* $EX; +^$CM+ $EX; # by rule 10, stand-alone CM behaves as AL + +$LB8NonBreaks $SY; +$CAN_CM $CM* $SY; +^$CM+ $SY; # by rule 10, stand-alone CM behaves as AL + + +# +# LB 14 Do not break after OP, even after spaces +# Note subtle interaction with "SP IS /" rules in LB14a. +# This rule consumes the SP, chaining happens on the IS, effectivley overriding the SP IS rules, +# which is the desired behavior. +# +$OP $CM* $SP* .; + +$OP $CM* $SP+ $CM+ $AL_FOLLOW?; # by rule 10, stand-alone CM behaves as AL + # by rule 8, CM following a SP is stand-alone. + + +# LB 14a Force a break before start of a number with a leading decimal pt, e.g. " .23" +# Note: would be simpler to express as "$SP / $IS $CM* $NU;", but ICU rules have limitations. +# See issue ICU-20303 + + +$CanFollowIS = [$BK $CR $LF $NL $SP $ZW $WJ $GL $CL $CP $EX $IS $SY $QU $BA $HY $NS $ALPlus $HL $IN]; +$SP $IS / [^ $CanFollowIS $NU $CM]; +$SP $IS $CM* $CMX / [^ $CanFollowIS $NU $CM]; + +# +# LB 14b Do not break before numeric separators (IS), even after spaces. + +[$LB8NonBreaks - $SP] $IS; +$SP $IS $CM* [$CanFollowIS {eof}]; +$SP $IS $CM* $ZWJ [^$CM $NU]; + +$CAN_CM $CM* $IS; +^$CM+ $IS; # by rule 10, stand-alone CM behaves as AL + + +# LB 15 +$QU $CM* $SP* $OP; + +# LB 16 +($CL | $CP) $CM* $SP* $NS; + +# LB 17 +$B2 $CM* $SP* $B2; + +# +# LB 18 Break after spaces. +# +$LB18NonBreaks = [$LB8NonBreaks - [$SP]]; +$LB18Breaks = [$LB8Breaks $SP]; + + +# LB 19 +# x QU +$LB18NonBreaks $CM* $QU; +^$CM+ $QU; + +# QU x +$QU $CM* .; + +# LB 20 +# <break> $CB +# $CB <break> +# +$LB20NonBreaks = [$LB18NonBreaks - $CB]; + +# LB 20.09 Don't break between Hyphens and Letters when there is a break preceding the hyphen. +# Originally added as a Finnish tailoring, now promoted to default ICU behavior. +# Note: this is not default UAX-14 behaviour. See issue ICU-8151. +# +^($HY | $HH) $CM* $ALPlus; + +# LB 21 x (BA | HY | NS) +# BB x +# +$LB20NonBreaks $CM* ($BA | $HY | $NS); + + +^$CM+ ($BA | $HY | $NS); + +$BB $CM* [^$CB]; # $BB x +$BB $CM* $LB20NonBreaks; + +# LB 21a Don't break after Hebrew + Hyphen +# HL (HY | BA) x +# +$HL $CM* ($HY | $BA) $CM* [^$CB]?; + +# LB 21b (forward) Don't break between SY and HL +# (break between HL and SY already disallowed by LB 13 above) +$SY $CM* $HL; + +# LB 22 Do not break before ellipses +# +$LB20NonBreaks $CM* $IN; +^$CM+ $IN; + + +# LB 23 +# +($ALPlus | $HL) $CM* $NU; +^$CM+ $NU; # Rule 10, any otherwise unattached CM behaves as AL +$NU $CM* ($ALPlus | $HL); + +# LB 23a +# +$PR $CM* ($ID | $EB | $EM); +($ID | $EB | $EM) $CM* $PO; + + +# +# LB 24 +# +($PR | $PO) $CM* ($ALPlus | $HL); +($ALPlus | $HL) $CM* ($PR | $PO); +^$CM+ ($PR | $PO); # Rule 10, any otherwise unattached CM behaves as AL + +# +# LB 25 Numbers. +# +(($PR | $PO) $CM*)? (($OP | $HY) $CM*)? ($IS $CM*)? $NU ($CM* ($NU | $SY | $IS))* + ($CM* ($CL | $CP))? ($CM* ($PR | $PO))?; + +# LB 26 Do not break a Korean syllable +# +$JL $CM* ($JL | $JV | $H2 | $H3); +($JV | $H2) $CM* ($JV | $JT); +($JT | $H3) $CM* $JT; + +# LB 27 Treat korean Syllable Block the same as ID (don't break it) +($JL | $JV | $JT | $H2 | $H3) $CM* $PO; +$PR $CM* ($JL | $JV | $JT | $H2 | $H3); + + +# LB 28 Do not break between alphabetics +# +($ALPlus | $HL) $CM* ($ALPlus | $HL); +^$CM+ ($ALPlus | $HL); # The $CM+ is from rule 10, an unattached CM is treated as AL + +# LB 29 +$IS $CM* ($ALPlus | $HL); + +# LB 30 +($ALPlus | $HL | $NU) $CM* $OP30; +^$CM+ $OP30; # The $CM+ is from rule 10, an unattached CM is treated as AL. +$CP30 $CM* ($ALPlus | $HL | $NU); + +# LB 30a Do not break between regional indicators. Break after pairs of them. +# Tricky interaction with LB8a: ZWJ x . together with ZWJ acting like a CM. +$RI $CM* $RI / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $IN $CM]]; +$RI $CM* $RI $CM* [$CM-$ZWJ] / [[^$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $IN $CM]]; +$RI $CM* $RI $CM* [$BK $CR $LF $NL $SP $ZW $WJ $CL $CP $EX $IS $SY $GL $QU $BA $HY $NS $IN $ZWJ {eof}]; +# note: the preceding rule includes {eof} rather than having the last [set] term qualified with '?' +# because of the chain-out behavior difference. The rule must chain out only from the [set characters], +# not from the preceding $RI or $CM, which it would be able to do if the set were optional. + +# LB30b Do not break between an emoji base (or potential emoji) and an emoji modifier. +$EB $CM* $EM; +$ExtPictUnassigned $CM* $EM; + +# LB 31 Break everywhere else. +# Match a single code point if no other rule applies. +.; |