#
#   Copyright (C) 2002-2013, International Business Machines Corporation and others.
#       All Rights Reserved.
#
#   file:  char.txt 
#
#   ICU Character Break Rules, also known as Grapheme Cluster Boundaries
#      See Unicode Standard Annex #29.
#      These rules are based on UAX #29 Revision 20 for Unicode Version 6.2
#

#
#  Character Class Definitions.
#
$CR          = [\p{Grapheme_Cluster_Break = CR}];
$LF          = [\p{Grapheme_Cluster_Break = LF}];
$Control     = [\p{Grapheme_Cluster_Break = Control}];
# TODO: Restore if the Prepend set becomes non-empty again: $Prepend     = [\p{Grapheme_Cluster_Break = Prepend}];
$Extend      = [\p{Grapheme_Cluster_Break = Extend}];
$SpacingMark = [\p{Grapheme_Cluster_Break = SpacingMark}];

$RI_A        = \U0001F1E6;  # Trail ERTU
$RI_B        = \U0001F1E7;  # Trail EGR
$RI_C        = \U0001F1E8;  # Trail AHLNZ
$RI_D        = \U0001F1E9;  # Trail EK
$RI_E        = \U0001F1EA;  # Trail GS
$RI_F        = \U0001F1EB;  # Trail IR
$RI_G        = \U0001F1EC;  # Trail BR
$RI_H        = \U0001F1ED;  # Trail KU
$RI_I        = \U0001F1EE;  # Trail DLNT
$RI_J        = \U0001F1EF;  # Trail OP
$RI_K        = \U0001F1F0;  # Trail R
$RI_L        = \U0001F1F1;  # Trail B
$RI_M        = \U0001F1F2;  # Trail OXY
$RI_N        = \U0001F1F3;  # Trail LO
$RI_P        = \U0001F1F5;  # Trail LT
$RI_R        = \U0001F1F7;  # Trail OU
$RI_S        = \U0001F1F8;  # Trail AEGK
$RI_T        = \U0001F1F9;  # Trail HRW
$RI_U        = \U0001F1FA;  # Trail AS
$RI_V        = \U0001F1FB;	# Trail N

$RI_A_End    = [\U0001F1EA \U0001F1F7 \U0001F1F9 \U0001F1FA];  	# ERTU
$RI_B_End    = [\U0001F1EA \U0001F1EC \U0001F1F7];              # EGR
$RI_C_End    = [\U0001F1E6 \U0001F1ED \U0001F1F1 \U0001F1F3 \U0001F1FF]; # AHLNZ
$RI_D_End    = [\U0001F1EA \U0001F1F0];                         # EK
$RI_E_End    = [\U0001F1EC \U0001F1F8];                         # GS
$RI_F_End    = [\U0001F1EE \U0001F1F7];                         # IR
$RI_G_End    = [\U0001F1E7 \U0001F1F7];                         # BR
$RI_H_End    = [\U0001F1F0 \U0001F1FA];                         # KU
$RI_I_End    = [\U0001F1E9 \U0001F1F1 \U0001F1F3 \U0001F1F9];	# DLNT
$RI_J_End    = [\U0001F1F4 \U0001F1F5];                         # OP
$RI_K_End    = \U0001F1F7;                                      # R
$RI_L_End    = \U0001F1E7;                                      # B
$RI_M_End    = [\U0001F1F4 \U0001F1FD \U0001F1FE];              # OXY
$RI_N_End    = [\U0001F1F1 \U0001F1F4];                         # LO
$RI_P_End    = [\U0001F1F1 \U0001F1F9];                         # LT
$RI_R_End    = [\U0001F1F4 \U0001F1FA];                         # OU
$RI_S_End    = [\U0001F1E6 \U0001F1EA \U0001F1EC \U0001F1F0];   # AEGK
$RI_T_End    = [\U0001F1ED \U0001F1F7 \U0001F1FC];              # HRW
$RI_U_End    = [\U0001F1E6 \U0001F1F8];                         # AS
$RI_V_End    = \U0001F1F3;                                      # N

#
# Korean Syllable Definitions
#
$L       = [\p{Grapheme_Cluster_Break = L}];
$V       = [\p{Grapheme_Cluster_Break = V}];
$T       = [\p{Grapheme_Cluster_Break = T}];

$LV      = [\p{Grapheme_Cluster_Break = LV}];
$LVT     = [\p{Grapheme_Cluster_Break = LVT}];


## -------------------------------------------------
!!chain;

!!forward;

$CR $LF;

$L ($L | $V | $LV | $LVT);
($LV | $V) ($V | $T);
($LVT | $T) $T;

$RI_A $RI_A_End;
$RI_B $RI_B_End;
$RI_C $RI_C_End;
$RI_D $RI_D_End;
$RI_E $RI_E_End;
$RI_F $RI_F_End;
$RI_G $RI_G_End;
$RI_H $RI_H_End;
$RI_I $RI_I_End;
$RI_J $RI_J_End;
$RI_K $RI_K_End;
$RI_L $RI_L_End;
$RI_M $RI_M_End;
$RI_N $RI_N_End;
$RI_P $RI_P_End;
$RI_R $RI_R_End;
$RI_S $RI_S_End;
$RI_T $RI_T_End;
$RI_U $RI_U_End;
$RI_V $RI_V_End;

[^$Control $CR $LF] $Extend;

[^$Control $CR $LF] $SpacingMark;
# TODO: Restore if the Prepend set becomes non-empty again: $Prepend [^$Control $CR $LF];


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

!!reverse;
$LF $CR;
($L | $V | $LV | $LVT) $L;
($V | $T) ($LV | $V);
$T ($LVT | $T);

$RI_A_End $RI_A;
$RI_B_End $RI_B;
$RI_C_End $RI_C;
$RI_D_End $RI_D;
$RI_E_End $RI_E;
$RI_F_End $RI_F;
$RI_G_End $RI_G;
$RI_H_End $RI_H;
$RI_I_End $RI_I;
$RI_J_End $RI_J;
$RI_K_End $RI_K;
$RI_L_End $RI_L;
$RI_M_End $RI_M;
$RI_N_End $RI_N;
$RI_P_End $RI_P;
$RI_R_End $RI_R;
$RI_S_End $RI_S;
$RI_T_End $RI_T;
$RI_U_End $RI_U;
$RI_V_End $RI_V;

$Extend      [^$Control $CR $LF];
$SpacingMark [^$Control $CR $LF];
# TODO: Restore if the Prepend set becomes non-empty again: [^$Control $CR $LF] $Prepend;


## -------------------------------------------------
#  We don't logically need safe char break rules, but if we don't provide any at all
#  the engine for preceding() and following() will fall back to the
#  old style inefficient algorithm.

!!safe_reverse;
$LF $CR;

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

!!safe_forward;
$CR $LF;