Files
gf-core/src-3.0/GF/Text/Ethiopic.hs

73 lines
2.0 KiB
Haskell

----------------------------------------------------------------------
-- |
-- Module : Ethiopic
-- Maintainer : HH
-- Stability : (stable)
-- Portability : (portable)
--
-- > CVS $Date: 2005/04/21 16:23:35 $
-- > CVS $Author: bringert $
-- > CVS $Revision: 1.6 $
--
-- Ascii-Unicode decoding for Ethiopian.
-- Copyright (c) Harald Hammarström 2003 under Gnu General Public License
-----------------------------------------------------------------------------
module GF.Text.Ethiopic (mkEthiopic) where
mkEthiopic :: String -> String
mkEthiopic = digraphWordToUnicode . adHocToDigraphWord
-- mkEthiopic :: String -> String
-- mkEthiopic = reverse . unwords . (map (digraphWordToUnicode . adHocToDigraphWord)) . words
--- reverse : assumes everything's on same line
adHocToDigraphWord :: String -> [(Char, Int)]
adHocToDigraphWord str = case str of
[] -> []
'<' : cs -> ('<', -1) : spoolMarkup cs
c1 : cs | isVowel c1 -> (')', vowelOrder c1) : adHocToDigraphWord cs
-- c1 isn't a vowel
c1 : cs | not (elem c1 allEthiopicCodes) -> (c1, -1) : adHocToDigraphWord cs
c1 : c2 : cs | isVowel c2 -> (c1, vowelOrder c2) : adHocToDigraphWord cs
c1 : cs -> (c1, 5) : adHocToDigraphWord cs
spoolMarkup :: String -> [(Char, Int)]
spoolMarkup s = case s of
-- [] -> [] -- Shouldn't happen
'>' : cs -> ('>', -1) : adHocToDigraphWord cs
c1 : cs -> (c1, -1) : spoolMarkup cs
isVowel x = elem x "A\228ui\239aeoI"
vowelOrder :: Char -> Int
vowelOrder x = case x of
'A' -> 0
'\228' -> 0 -- ä
'u' -> 1
'i' -> 2
'a' -> 3
'e' -> 4
'I' -> 5
'\239' -> 5 -- ï
'o' -> 6
c -> 5 -- vowelless
digraphWordToUnicode = map digraphToUnicode
digraphToUnicode :: (Char, Int) -> Char
-- digraphToUnicode (c1, c2) = c1
digraphToUnicode (c1, -1) = c1
digraphToUnicode (c1, c2) = toEnum (0x1200 + c2 + 8*case lookup c1 cc of Just c' -> c')
where
cc = zip allEthiopicCodes allEthiopic
allEthiopic :: [Int]
allEthiopic = [0 .. 44] -- x 8
allEthiopicCodes = "hlHmLrs$KQ__bBtcxXnN)kW__w(zZyd_jgG_TCPSLfp"
-- Q = kW, X = xW, W = kW, G = gW