NKF - Ruby extension for Network Kanji Filter
Description
This is a Ruby Extension version of nkf (Network Kanji Filter). It converts the first argument and returns converted result. Conversion details are specified by flags as the first argument.
Nkf is a yet another kanji code converter among networks, hosts and terminals. It converts input kanji code to designated kanji code such as ISO-2022-JP, Shift_JIS, EUC-JP, UTF-8 or UTF-16.
One of the most unique faculty of nkf is the guess of the input kanji encodings. It currently recognizes ISO-2022-JP, Shift_JIS, EUC-JP, UTF-8 and UTF-16. So users needn’t set the input kanji code explicitly.
By default, X0201 kana is converted into X0208 kana. For X0201 kana, SO/SI, SSO and ESC-(-I methods are supported. For automatic code detection, nkf assumes no X0201 kana in Shift_JIS. To accept X0201 in Shift_JIS, use -X, -x or -S.
Flags
-b -u
Output is buffered (DEFAULT), Output is unbuffered.
-j -s -e -w -w16 -w32
Output code is ISO-2022-JP (7bit JIS), Shift_JIS, EUC-JP, UTF-8N, UTF-16BE, UTF-32BE. Without this option and compile option, ISO-2022-JP is assumed.
-J -S -E -W -W16 -W32
Input assumption is JIS 7 bit, Shift_JIS, EUC-JP, UTF-8, UTF-16, UTF-32.
-J
Assume JIS input. It also accepts EUC-JP. This is the default. This flag does not exclude Shift_JIS.
-S
Assume Shift_JIS and X0201 kana input. It also accepts JIS. EUC-JP is recognized as X0201 kana. Without -x flag, X0201 kana (halfwidth kana) is converted into X0208.
-E
Assume EUC-JP input. It also accepts JIS. Same as -J.
-t
No conversion.
-i_
Output sequence to designate JIS-kanji. (DEFAULT B)
-o_
Output sequence to designate ASCII. (DEFAULT B)
-r
{de/en}crypt ROT13/47
-h[123] –hiragana –katakana –katakana-hiragana
- -h1 –hiragana
-
Katakana to Hiragana conversion.
- -h2 –katakana
-
Hiragana to Katakana conversion.
- -h3 –katakana-hiragana
-
Katakana to Hiragana and Hiragana to Katakana conversion.
-T
Text mode output (MS-DOS)
-l
ISO8859-1 (Latin-1) support
-f[m [- n]]
Folding on m length with n margin in a line. Without this option, fold length is 60 and fold margin is 10.
-F
New line preserving line folding.
-Z[0-3]
Convert X0208 alphabet (Fullwidth Alphabets) to ASCII.
- -Z -Z0
-
Convert X0208 alphabet to ASCII.
- -Z1
-
Converts X0208 kankaku to single ASCII space.
- -Z2
-
Converts X0208 kankaku to double ASCII spaces.
- -Z3
-
Replacing Fullwidth >, <, “, & into ‘>’, ‘<’, ‘"’, ‘&’ as in HTML.
-X -x
Assume X0201 kana in MS-Kanji. With -X or without this option, X0201 is converted into X0208 Kana. With -x, try to preserve X0208 kana and do not convert X0201 kana to X0208. In JIS output, ESC-(-I is used. In EUC output, SSO is used.
-B[0-2]
Assume broken JIS-Kanji input, which lost ESC. Useful when your site is using old B-News Nihongo patch.
- -B1
-
allows any char after ESC-( or ESC-$.
- -B2
-
forces ASCII after NL.
-I
Replacing non iso-2022-jp char into a geta character (substitute character in Japanese).
-d -c
Delete r in line feed, Add r in line feed.
-m[BQN0]
MIME ISO-2022-JP/ISO8859-1 decode. (DEFAULT) To see ISO8859-1 (Latin-1) -l is necessary.
- -mB
-
Decode MIME base64 encoded stream. Remove header or other part before
conversion.
- -mQ
-
Decode MIME quoted stream. ‘_’ in quoted stream is converted to space.
- -mN
-
Non-strict decoding.
It allows line break in the middle of the base64 encoding.
- -m0
-
No MIME decode.
-M
MIME encode. Header style. All ASCII code and control characters are intact. Kanji conversion is performed before encoding, so this cannot be used as a picture encoder.
- -MB
-
MIME encode Base64 stream.
- -MQ
-
Perfome quoted encoding.
-l
Input and output code is ISO8859-1 (Latin-1) and ISO-2022-JP. -s, -e and -x are not compatible with this option.
-L[uwm]
new line mode Without this option, nkf doesn’t convert line breaks.
- -Lu
-
unix (LF)
- -Lw
-
windows (CRLF)
- -Lm
-
mac (CR)
–fj –unix –mac –msdos –windows
convert for these system
–jis –euc –sjis –mime –base64
convert for named code
–jis-input –euc-input –sjis-input –mime-input –base64-input
assume input system
–ic=input codeset –oc=output codeset
Set the input or output codeset. NKF supports following codesets and those codeset name are case insensitive.
- ISO-2022-JP
-
a.k.a. RFC1468, 7bit JIS, JUNET
- EUC-JP (eucJP-nkf)
-
a.k.a. AT&T JIS, Japanese EUC, UJIS
- eucJP-ascii
-
a.k.a. x-eucjp-open-19970715-ascii
- eucJP-ms
-
a.k.a. x-eucjp-open-19970715-ms
- CP51932
-
Microsoft Version of EUC-JP.
- Shift_JIS
-
SJIS, MS-Kanji
- Windows-31J
-
a.k.a. CP932
- UTF-8
-
same as UTF-8N
- UTF-8N
-
UTF-8 without BOM
- UTF-8-BOM
-
UTF-8 with BOM
- UTF-16
-
same as UTF-16BE
- UTF-16BE
-
UTF-16 Big Endian without BOM
- UTF-16BE-BOM
-
UTF-16 Big Endian with BOM
- UTF-16LE
-
UTF-16 Little Endian without BOM
- UTF-16LE-BOM
-
UTF-16 Little Endian with BOM
- UTF-32
-
same as UTF-32BE
- UTF-32BE
-
UTF-32 Big Endian without BOM
- UTF-32BE-BOM
-
UTF-32 Big Endian with BOM
- UTF-32LE
-
UTF-32 Little Endian without BOM
- UTF-32LE-BOM
-
UTF-32 Little Endian with BOM
- UTF8-MAC
-
NKDed UTF-8, a.k.a. UTF8-NFD (input only)
–fb-{skip, html, xml, perl, java, subchar}
Specify the way that nkf handles unassigned characters. Without this option, –fb-skip is assumed.
–prefix= escape character target character ..
When nkf converts to Shift_JIS, nkf adds a specified escape character to specified 2nd byte of Shift_JIS characters. 1st byte of argument is the escape character and following bytes are target characters.
–no-cp932ext
Handle the characters extended in CP932 as unassigned characters.
–no-best-fit-chars
When Unicode to Encoded byte conversion, don’t convert characters which is not round trip safe. When Unicode to Unicode conversion, with this and -x option, nkf can be used as UTF converter. (In other words, without this and -x option, nkf doesn’t save some characters)
When nkf convert string which related to path, you should use this opion.
–cap-input
Decode hex encoded characters.
–url-input
Unescape percent escaped characters.
–
Ignore rest of -option.
Constants
NKF_RELEASE_DATE = rb_str_new2(NKF_RELEASE_DATE)
NKF_VERSION = rb_str_new2(NKF_VERSION)
VERSION = rb_str_new2(RUBY_NKF_VERSION)
UTF32 = rb_enc_from_encoding(rb_nkf_enc_get("UTF-32BE"))
UTF16 = rb_enc_from_encoding(rb_nkf_enc_get("UTF-16BE"))
UTF8 = rb_enc_from_encoding(rb_utf8_encoding())
SJIS = rb_enc_from_encoding(rb_nkf_enc_get("Shift_JIS"))
EUC = rb_enc_from_encoding(rb_nkf_enc_get("EUC-JP"))
JIS = rb_enc_from_encoding(rb_nkf_enc_get("ISO-2022-JP"))
ASCII = rb_enc_from_encoding(rb_nkf_enc_get("US-ASCII"))
BINARY = rb_enc_from_encoding(rb_nkf_enc_get("BINARY"))
UNKNOWN = Qnil
NOCONV = Qnil
AUTO = Qnil