#
# 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: word.txt
#
# ICU Word Break Rules (modified from standard to remove colon from $MidLetter)
# See Unicode Standard Annex #29.
# These rules are based on UAX #29 Revision 34 for Unicode Version 12.0
#
# Note: Updates to word.txt will usually need to be merged into
# word_POSIX.txt also.
##############################################################################
#
# Character class definitions from TR 29
#
##############################################################################
!!chain;
!!quoted_literals_only;
#
# Character Class Definitions.
#
$Han = [:Han:];
$CR = [\p{Word_Break = CR}];
$LF = [\p{Word_Break = LF}];
$Newline = [\p{Word_Break = Newline}];
$Extend = [\p{Word_Break = Extend}-$Han];
$ZWJ = [\p{Word_Break = ZWJ}];
$Regional_Indicator = [\p{Word_Break = Regional_Indicator}];
$Format = [\p{Word_Break = Format}];
$Katakana = [\p{Word_Break = Katakana}];
$Hebrew_Letter = [\p{Word_Break = Hebrew_Letter}];
$ALetter = [\p{Word_Break = ALetter}];
$Single_Quote = [\p{Word_Break = Single_Quote}];
$Double_Quote = [\p{Word_Break = Double_Quote}];
$MidNumLet = [\p{Word_Break = MidNumLet}];
$MidLetter = [\p{Word_Break = MidLetter} - [\:]];
$MidNum = [\p{Word_Break = MidNum}];
$Numeric = [\p{Word_Break = Numeric}];
$ExtendNumLet = [\p{Word_Break = ExtendNumLet}];
$WSegSpace = [\p{Word_Break = WSegSpace}];
$Extended_Pict = [\p{Extended_Pictographic}];
$Hiragana = [:Hiragana:];
$Ideographic = [\p{Ideographic}];
# Dictionary character set, for triggering language-based break engines. Currently
# limited to LineBreak=Complex_Context. Note that this set only works in Unicode
# 5.0 or later as the definition of Complex_Context was corrected to include all
# characters requiring dictionary break.
$Control = [\p{Grapheme_Cluster_Break = Control}];
$HangulSyllable = [\uac00-\ud7a3];
$ComplexContext = [:LineBreak = Complex_Context:];
$KanaKanji = [$Han $Hiragana $Katakana];
$dictionaryCJK = [$KanaKanji $HangulSyllable];
$dictionary = [$ComplexContext $dictionaryCJK];
# TODO: check if handling of katakana in dictionary makes rules incorrect/void
# leave CJK scripts out of ALetterPlus
$ALetterPlus = [$ALetter-$dictionaryCJK [$ComplexContext-$Extend-$Control]];
## -------------------------------------------------
# Rule 3 - CR x LF
#
$CR $LF;
# Rule 3c Do not break within emoji zwj sequences.
# ZWJ × \p{Extended_Pictographic}. Precedes WB4, so no intervening Extend chars allowed.
#
$ZWJ $Extended_Pict;
# Rule 3d - Keep horizontal whitespace together.
#
$WSegSpace $WSegSpace;
# Rule 4 - ignore Format and Extend characters, except when they appear at the beginning
# of a region of Text.
$ExFm = [$Extend $Format $ZWJ];
^$ExFm+; # This rule fires only when there are format or extend characters at the
# start of text, or immediately following another boundary. It groups them, in
# the event there are more than one.
[^$CR $LF $Newline $ExFm] $ExFm*; # This rule rule attaches trailing format/extends to words,
# with no special rule status value.
$Numeric $ExFm* {100}; # This group of rules also attach trailing format/extends, but
$ALetterPlus $ExFm* {200}; # with rule status set based on the word's final base character.
$HangulSyllable {200};
$Hebrew_Letter $ExFm* {200};
$Katakana $ExFm* {400}; # note: these status values override those from rule 5
$Hiragana $ExFm* {400}; # by virtue of being numerically larger.
$Ideographic $ExFm* {400}; #
#
# rule 5
# Do not break between most letters.
#
($ALetterPlus | $Hebrew_Letter) $ExFm* ($ALetterPlus | $Hebrew_Letter);
# rule 6 and 7
($ALetterPlus | $Hebrew_Letter) $ExFm* ($MidLetter | $MidNumLet | $Single_Quote) $ExFm* ($ALetterPlus | $Hebrew_Letter) {200};
# rule 7a
$Hebrew_Letter $ExFm* $Single_Quote {200};
# rule 7b and 7c
$Hebrew_Letter $ExFm* $Double_Quote $ExFm* $Hebrew_Letter;
# rule 8
$Numeric $ExFm* $Numeric;
# rule 9
($ALetterPlus | $Hebrew_Letter) $ExFm* $Numeric;
# rule 10
$Numeric $ExFm* ($ALetterPlus | $Hebrew_Letter);
# rule 11 and 12
$Numeric $ExFm* ($MidNum | $MidNumLet | $Single_Quote) $ExFm* $Numeric;
# rule 13
# to be consistent with $KanaKanji $KanaKanhi, changed
# from 300 to 400.
# See also TestRuleStatus in intltest/rbbiapts.cpp
$Katakana $ExFm* $Katakana {400};
# rule 13a/b
$ALetterPlus $ExFm* $ExtendNumLet {200}; # (13a)
$Hebrew_Letter $ExFm* $ExtendNumLet {200}; # (13a)
$Numeric $ExFm* $ExtendNumLet {100}; # (13a)
$Katakana $ExFm* $ExtendNumLet {400}; # (13a)
$ExtendNumLet $ExFm* $ExtendNumLet {200}; # (13a)
$ExtendNumLet $ExFm* $ALetterPlus {200}; # (13b)
$ExtendNumLet $ExFm* $Hebrew_Letter {200}; # (13b)
$ExtendNumLet $ExFm* $Numeric {100}; # (13b)
$ExtendNumLet $ExFm* $Katakana {400}; # (13b)
# rules 15 - 17
# Pairs of Regional Indicators stay together.
# With incoming rule chaining disabled by ^, this rule will match exactly two of them.
# No other rule begins with a Regional_Indicator, so chaining cannot extend the match.
#
^$Regional_Indicator $ExFm* $Regional_Indicator;
# special handling for CJK characters: chain for later dictionary segmentation
$HangulSyllable $HangulSyllable {200};
$KanaKanji $KanaKanji {400}; # different rule status if both kana and kanji found
# Rule 999
# Match a single code point if no other rule applies.
.;