# Copyright (C) 2016 and later: Unicode, Inc. and others.
# License & terms of use: http://www.unicode.org/copyright.html
#
#   Copyright (C) 2002-2015, International Business Machines Corporation and others.
#       All Rights Reserved.
#
#   file:  sent.txt
#
#   ICU Sentence Break Rules
#      See Unicode Standard Annex #29.
#      These rules are based on UAX #29 Revision 34 for Unicode Version 12.0
#

!!quoted_literals_only;

#
# Character categories as defined in TR 29
#
$CR        = [\p{Sentence_Break = CR}];
$LF        = [\p{Sentence_Break = LF}];
$Extend    = [\p{Sentence_Break = Extend}];
$Sep       = [\p{Sentence_Break = Sep}];
$Format    = [\p{Sentence_Break = Format}];
$Sp        = [\p{Sentence_Break = Sp}];
$Lower     = [\p{Sentence_Break = Lower}];
$Upper     = [\p{Sentence_Break = Upper}];
$OLetter   = [\p{Sentence_Break = OLetter}];
$Numeric   = [\p{Sentence_Break = Numeric}];
$ATerm     = [\p{Sentence_Break = ATerm}];
$SContinue = [\p{Sentence_Break = SContinue}];
$STerm     = [\p{Sentence_Break = STerm}];
$Close     = [\p{Sentence_Break = Close}];

#
# Define extended forms of the character classes,
#   incorporate trailing Extend or Format chars.
#   Rules 4 and 5.

$SpEx       = $Sp      ($Extend | $Format)*;
$LowerEx    = $Lower   ($Extend | $Format)*;
$UpperEx    = $Upper   ($Extend | $Format)*;
$OLetterEx  = $OLetter ($Extend | $Format)*;
$NumericEx  = $Numeric ($Extend | $Format)*;
$ATermEx    = $ATerm   ($Extend | $Format)*;
$SContinueEx= $SContinue ($Extend | $Format)*;
$STermEx    = $STerm   ($Extend | $Format)*;
$CloseEx    = $Close   ($Extend | $Format)*;


## -------------------------------------------------

!!chain;

# Rule 3 - break after separators.  Keep CR/LF together.
#
$CR $LF;


# Rule 4 - Break after $Sep.
# Rule 5 - Ignore $Format and $Extend
#
[^$Sep $CR $LF]? ($Extend | $Format)*;


# Rule 6
$ATermEx $NumericEx;

# Rule 7
($UpperEx | $LowerEx) $ATermEx $UpperEx;

#Rule 8
$NotLettersEx = [^$OLetter $Upper $Lower $Sep $CR $LF $ATerm $STerm] ($Extend | $Format)*;
$ATermEx $CloseEx* $SpEx* $NotLettersEx* $Lower;

# Rule 8a
($STermEx | $ATermEx) $CloseEx* $SpEx* ($SContinueEx | $STermEx | $ATermEx);

#Rule 9, 10, 11
($STermEx | $ATermEx) $CloseEx* $SpEx* ($Sep | $CR | $LF)?;

#Rule 998
[[^$STerm $ATerm $Close $Sp $Sep $LF $CR $Format $Extend]{bof}] ($Extend | $Format | $Close | $Sp)* .;
[[^$STerm $ATerm $Close $Sp $Sep $LF $CR $Format $Extend]{bof}] ($Extend | $Format | $Close | $Sp)* ([$Sep $LF $CR {eof}] | $CR $LF){100};