Files
gf-core/src/GF/Text/Transliterations.hs
2009-08-27 13:47:57 +00:00

206 lines
8.0 KiB
Haskell

module GF.Text.Transliterations (
transliterate,
transliteration,
characterTable,
transliterationPrintNames
) where
import GF.Text.UTF8
import Data.Char
import Numeric
import qualified Data.Map as Map
-- transliterations between ASCII and a Unicode character set
-- current transliterations: devanagari, thai
-- to add a new one: define the Unicode range and the corresponding ASCII strings,
-- which may be one or more characters long
-- conventions to be followed:
-- each character is either [letter] or [letter+nonletters]
-- when using a sparse range of unicodes, mark missing codes as "-" in transliterations
-- characters can be invisible: ignored in translation to unicode
transliterate :: String -> Maybe (String -> String)
transliterate s = case s of
'f':'r':'o':'m':'_':t -> fmap appTransFromUnicode $ transliteration t
't':'o':'_':t -> fmap appTransToUnicode $ transliteration t
_ -> Nothing
transliteration :: String -> Maybe Transliteration
transliteration s = Map.lookup s allTransliterations
allTransliterations = Map.fromAscList [
("ancientgreek", transAncientGreek),
("arabic", transArabic),
("devanagari", transDevanagari),
("greek", transGreek),
("hebrew", transHebrew),
("persian", transPersian),
("telugu", transTelugu),
("thai", transThai)
---- "urdu", transUrdu
]
-- used in command options and help
transliterationPrintNames = [(t,printname p) | (t,p) <- Map.toList allTransliterations]
characterTable :: Transliteration -> String
characterTable = unlines . map prOne . Map.assocs . trans_from_unicode where
prOne (i,s) = unwords ["|", showHex i "", "|", [toEnum i], "|", s, "|"]
data Transliteration = Trans {
trans_to_unicode :: Map.Map String Int,
trans_from_unicode :: Map.Map Int String,
invisible_chars :: [String],
printname :: String
}
appTransToUnicode :: Transliteration -> String -> String
appTransToUnicode trans =
concat .
map (\c -> maybe c (return . toEnum) $
Map.lookup c (trans_to_unicode trans)
) .
filter (flip notElem (invisible_chars trans)) .
unchar
appTransFromUnicode :: Transliteration -> String -> String
appTransFromUnicode trans =
concat .
map (maybe "?" id .
flip Map.lookup (trans_from_unicode trans)
) .
map fromEnum
mkTransliteration :: String -> [String] -> [Int] -> Transliteration
mkTransliteration name ts us =
Trans (Map.fromList (tzip ts us)) (Map.fromList (uzip us ts)) [] name
where
tzip ts us = [(t,u) | (t,u) <- zip ts us, t /= "-"]
uzip us ts = [(u,t) | (u,t) <- zip us ts, t /= "-"]
unchar :: String -> [String]
unchar s = case s of
c:d:cs
| isAlpha d -> [c] : unchar (d:cs)
| isSpace d -> [c]:[d]: unchar cs
| otherwise -> let (ds,cs2) = break (\x -> isAlpha x || isSpace x) cs in
(c:d:ds) : unchar cs2
[_] -> [s]
_ -> []
transThai :: Transliteration
transThai = mkTransliteration "Thai" allTrans allCodes where
allTrans = words $
"- k k1 - k2 - k3 g c c1 c2 s' c3 y' d' t' " ++
"t1 t2 t3 n' d t t4 t5 t6 n b p p1 f p2 f' " ++
"p3 m y r - l - w s- s. s h l' O h' - " ++
"a. a a: a+ i i: v v: u u: - - - - - - " ++
"e e' o: a% a& L R S T1 T2 T3 T4 K - - - " ++
"N0 N1 N2 N3 N4 N5 N6 N7 N8 N9 - - - - - - "
allCodes = [0x0e00 .. 0x0e7f]
transDevanagari :: Transliteration
transDevanagari =
(mkTransliteration "Devanagari"
allTransUrduHindi allCodes){invisible_chars = ["a"]} where
allCodes = [0x0900 .. 0x095f]
allTransUrduHindi = words $
"- M N - - a- A- i- I- u- U- R- - - - e- " ++
"E- - - o- O- k K g G N: c C j J n: t. " ++
"T. d. D. n. t T d D n - p P b B m y " ++
"r - l - - v S s. s h - - r: - A i " ++
"I u U R - - - e E o O - - - - - " ++
"- - - - - - - - - - - z r. - - - "
transUrdu :: Transliteration
transUrdu =
(mkTransliteration "Urdu" allTransUrduHindi allCodes){invisible_chars = ["a"]} where
allCodes = [0x0900 .. 0x095f] ---- TODO: this is devanagari
transArabic :: Transliteration
transArabic = mkTransliteration "Arabic" allTrans allCodes where
allTrans = words $
" V A: A? w? A- y? A b t. t v g H K d " ++ -- 0621 - 062f
"W r z s C S D T Z c G " ++ -- 0630 - 063a
" f q k l m n h w y. y a. u. i. a u " ++ -- 0641 - 064f
"i v2 o a: V+ V- i: a+" -- 0650 - 0657
allCodes = [0x0621..0x062f] ++ [0x0630..0x063a] ++
[0x0641..0x064f] ++ [0x0650..0x0657]
transPersian :: Transliteration
transPersian = (mkTransliteration "Persian/Farsi" allTrans allCodes)
{invisible_chars = ["a","u","i"]} where
allTrans = words $
" V A: A? w? A- y? A b t. t t- j H K d " ++ -- 0621 - 062f
"W r z s C S D T Z c G " ++ -- 0630 - 063a
" f q k l m n h v y. y a. u. i. a u " ++ -- 0641 - 064f
"i v2 o a: V+ V- i: a+ " ++ -- 0650 - 0657
"p c^ J g "
allCodes = [0x0621..0x062f] ++ [0x0630..0x063a] ++
[0x0641..0x064f] ++ [0x0650..0x0657] ++
[0x067e,0x0686,0x0698,0x06af]
transHebrew :: Transliteration
transHebrew = mkTransliteration "unvocalized Hebrew" allTrans allCodes where
allTrans = words $
"A b g d h w z H T y K k l M m N " ++
"n S O P p Z. Z q r s t - - - - - " ++
"w2 w3 y2 g1 g2"
allCodes = [0x05d0..0x05f4]
transTelugu :: Transliteration
transTelugu = mkTransliteration "Telugu" allTrans allCodes where
allTrans = words $
"- c1 c2 c3 - A A: I I: U U: R_ L_ - E E: " ++
"A' - O O: A_ k k. g g. n. c c. j j. n' T " ++
"T. d d. N t t. d d. n - p p. b b. m y " ++
"r R l L - v s' S s h - - - c5 a: i " ++
"i: u u: r_ r. - e e: a' - o o: a_ c6 - - " ++
"- - - - - c7 c8 z Z - - - - - - - " ++
"R+ L+ l+ l* - - n0 n1 n2 n3 n4 n5 n6 n7 n8 n9 "
allCodes = [0x0c00 .. 0x0c7f]
transGreek :: Transliteration
transGreek = mkTransliteration "modern Greek" allTrans allCodes where
allTrans = words $
"- - - - - - A' - E' H' I' - O' - Y' W' " ++
"i= A B G D E Z H V I K L M N X O " ++
"P R - S T Y F C Q W I- Y- a' e' h' i' " ++
"y= a b g d e z h v i k l m n x o " ++
"p r s* s t y f c q w i- y- o' y' w' - "
allCodes = [0x0380 .. 0x03cf]
transAncientGreek :: Transliteration
transAncientGreek = mkTransliteration "ancient Greek" allTrans allCodes where
allTrans = words $
"- - - - - - - - - - - - - - - - " ++
"i= A B G D E Z H V I K L M N X O " ++
"P R - S T Y F C Q W I- Y- - - - - " ++
"y= a b g d e z h v i k l m n x o " ++
"p r s* s t y f c q w i- y- - - - - " ++
"a) a( a)` a(` a)' a(' a)~ a(~ A) A( A)` A(` A)' A(' A)~ A(~ " ++
"e) e( e)` e(` e)' e(' - - E) E( E)` E(` E)' E(' - - " ++
"h) h( h)` h(` h)' h(' h)~ h(~ H) H( H)` H(` H)' H(' H)~ H(~ " ++
"i) i( i)` i(` i)' i(' i)~ i(~ I) I( I)` I(` I)' I(' I)~ I(~ " ++
"o) o( o)` o(` o)' o(' - - O) O( O)` O(` O)' O(' - - " ++
"y) y( y)` y(` y)' y(' y)~ y(~ - Y( - Y(` - Y(' - Y(~ " ++
"w) w( w)` w(` w)' w(' w)~ w(~ W) W( W)` W(` W)' W(' W)~ W(~ " ++
"a` a' e` e' h` h' i` i' o` o' y` y' w` w' - - " ++
"a|( a|) a|)` a|(` a|)' a|(' a|)~ a|(~ - - - - - - - - " ++ -- 1f80-
"h|( h|) h|)` h|(` h|)' h|(' h|)~ h|(~ - - - - - - - - " ++ -- 1f90-
"w|( w|) w|)` w|(` w|)' w|(' w|)~ w|(~ - - - - - - - - " ++ -- 1fa0-
"a. a_ a|` a| a|' - a~ a|~ - - - - - - - - " ++ -- 1fb0-
"- - h|` h| h|' - h~ h|~ - - - - - - - - " ++ -- 1fc0-
"i. i_ i=` i=' - - i~ i=~ - - - - - - - - " ++ -- 1fd0-
"y. y_ y=` y=' r) r( y~ y|~ - - - - - - - - " ++ -- 1fe0-
"- - w|` w| w|' - w~ w|~ - - - - - - - - " -- 1ff0-
allCodes = [0x0380 .. 0x03cf] ++ [0x1f00 .. 0x1fff]