﻿#--------------------------------------------------------------------
# Copyright (c) 1999-2001, International Business Machines
# Corporation and others.  All Rights Reserved.
#--------------------------------------------------------------------
# Date: Tue Jan 23 2001
#--------------------------------------------------------------------

# note: a global filter is more efficient, but MUST include all source chars
:: [\u0000-\u007E \u3001\u3002 \u3099-\u309C \u30A1-\u30FC \uFF61-\uFF9Fー[:Hiragana:] [:Katakana:] [:nonspacing mark:]] ;
:: NFKC ();

# Hiragana-Katakana

# This is largely a one-to-one mapping, but it has a
# few kinks:

# 1. The Katakana va/vi/ve/vo (30F7-30FA) have no
# Hiragana equivalents.  We use Hiragana wa/wi/we/wo
# (308F-3092) with a voicing mark (3099), which is
# semantically equivalent.  However, this is a non-
# roundtripping transformation.

# 2. The Katakana small ka/ke (30F5,30F6) have no
# Hiragana equiavlents.  We convert them to normal
# Hiragana ka/ke (304B,3051).  This is a one-way
# information-losing transformation and precludes
# round-tripping of 30F5 and 30F6.

# 3. The combining marks 3099-309C are in the Hiragana
# block, but they apply to Katakana as well, so we
# leave them untouched.

# 4. The Katakana prolonged sound mark 30FC doubles the
# preceding vowel.  This is a one-way information-
# losing transformation from Katakana to Hiragana.

# 5. The Katakana middle dot separates words in foreign
# expressions; we leave this unmodified.

# The above points preclude successful round-trip
# transformations of arbitrary input text.  However,
# they provide naturalistic results that should conform
# to user expectations.


# Combining equivalents va/vi/ve/vo
わ゙ <> ヷ;
ゐ゙ <> ヸ;
ゑ゙ <> ヹ;
を゙ <> ヺ;

# One-to-one mappings, main block
# 3041:3094 <> 30A1:30F4
# 309D,E <> 30FD,E
ぁ <> ァ;
あ <> ア;
ぃ <> ィ;
い <> イ;
ぅ <> ゥ;
う <> ウ;
ぇ <> ェ;
え <> エ;
ぉ <> ォ;
お <> オ;
か <> カ;
が <> ガ;
き <> キ;
ぎ <> ギ;
く <> ク;
ぐ <> グ;
け <> ケ;
げ <> ゲ;
こ <> コ;
ご <> ゴ;
さ <> サ;
ざ <> ザ;
し <> シ;
じ <> ジ;
す <> ス;
ず <> ズ;
せ <> セ;
ぜ <> ゼ;
そ <> ソ;
ぞ <> ゾ;
た <> タ;
だ <> ダ;
ち <> チ;
ぢ <> ヂ;
っ <> ッ;
つ <> ツ;
づ <> ヅ;
て <> テ;
で <> デ;
と <> ト;
ど <> ド;
な <> ナ;
に <> ニ;
ぬ <> ヌ;
ね <> ネ;
の <> ノ;
は <> ハ;
ば <> バ;
ぱ <> パ;
ひ <> ヒ;
び <> ビ;
ぴ <> ピ;
ふ <> フ;
ぶ <> ブ;
ぷ <> プ;
へ <> ヘ;
べ <> ベ;
ぺ <> ペ;
ほ <> ホ;
ぼ <> ボ;
ぽ <> ポ;
ま <> マ;
み <> ミ;
む <> ム;
め <> メ;
も <> モ;
ゃ <> ャ;
や <> ヤ;
ゅ <> ュ;
ゆ <> ユ;
ょ <> ョ;
よ <> ヨ;
ら <> ラ;
り <> リ;
る <> ル;
れ <> レ;
ろ <> ロ;
ゎ <> ヮ;
わ <> ワ;
ゐ <> ヰ;
ゑ <> ヱ;
を <> ヲ;
ん <> ン;
ゔ <> ヴ;
ゝ <> ヽ;
ゞ <> ヾ;

# One-way Katakana-Hiragana xform of small K ka/ke to
# normal H ka/ke.
か < ヵ;
け < ヶ;

# Katakana followed by a prolonged sound mark 30FC has
# its final vowel doubled.  This is a Katakana-Hiragana
# one-way information-losing transformation.  We
# include the small Katakana (e.g., small A 3041) and
# do not distinguish them from their large
# counterparts.  It doesn't make sense to double a
# small counterpart vowel as a small Hiragana vowel, so
# we don't do so.  In natural text this should never
# occur anyway.  If a 30FC is seen without a preceding
# vowel sound (e.g., after n 30F3) we do not change it.

### $long = ー;

# The following categories are Hiragana, not Katakana
# as might be expected, since by the time we get to the
# 30FC, the preceding character will have already been
# transformed to Hiragana.

# {The following mechanically generated from the
# Unicode 3.0 data:}

$xa = [ \
ぁ あ か が さ ざ \
た だ な は ば ぱ \
ま ゃ や ら ゎ わ \
];

$xi = [ \
ぃ い き ぎ し じ \
ち ぢ に ひ び ぴ \
み り ゐ \
];

$xu = [ \
ぅ う く ぐ す ず \
っ つ づ ぬ ふ ぶ \
ぷ む ゅ ゆ る ゔ \
];

$xe = [ \
ぇ え け げ せ ぜ \
て で ね へ べ ぺ \
め れ ゑ \
];

$xo = [ \
ぉ お こ ご そ ぞ \
と ど の ほ ぼ ぽ \
も ょ よ ろ を \
];

あ < $xa {ー};
い < $xi {ー};
う < $xu {ー};
え < $xe {ー};
お < $xo {ー};

:: (NFKC) ;

# note: a global filter is more efficient, but MUST include all source chars!!
:: ([\u0000-\u007E \u3001\u3002 \u3099-\u309C \u30A1-\u30FC \uFF61-\uFF9Fー[:Hiragana:] [:Katakana:] [:nonspacing mark:]]);

# eof