1 files changed, 310 insertions, 0 deletions

diff --git a/src/runtime/haskell/PGF/LexingAGreek.hs b/src/runtime/haskell/PGF/LexingAGreek.hs
new file mode 100644
index 000000000..a8ed19238
--- /dev/null
+++ b/src/runtime/haskell/PGF/LexingAGreek.hs
@@ -0,0 +1,310 @@
+module PGF.LexingAGreek where                      -- HL 2a1.2.2016
+import Data.Char(isSpace)
+
+-- * Text lexing without word capitalization of the first word of every sentence.
+-- Greek sentences in (transliterated) texts don't start with capital character. 
+
+-- Ordinary greek text does not have vowel length indicators. We then use '.' as
+-- a sentence separator.
+
+lexTextAGreek :: String -> [String]
+lexTextAGreek s = lext s where
+  lext s = case s of
+    c:cs | isAGreekPunct c -> [c] : (lext cs)
+    c:cs | isSpace c -> lext cs
+    _:_ -> let (w,cs) = break (\x -> isSpace x || isAGreekPunct x) s 
+           in w : lext cs
+    [] -> []
+
+-- Philological greek text may use vowel length indicators. Then '.' is not a sentence 
+-- separator, nor is 'v. ' for vowel v. Sentence ends at 'v..' or 'c. ' with non-vowel c.
+
+lexTextAGreek2 :: String -> [String]
+lexTextAGreek2 s = lext s where
+  lext s = case s of
+    c:cs | isAGreekPunct c -> [c] : (lext cs)
+    c:cs | isSpace c -> lext cs
+    _:_ -> let (w,cs) = break (\x -> isSpace x || isAGreekPunct x) s 
+           in case cs of 
+                '.':'.':d:ds | isSpace d 
+                  -> (w++['.']) : lext ('.':d:ds)
+                '.':d:ds | isAGreekPunct d || isSpace d 
+                  -> (w++['.']) : lext (d:ds)
+                '.':d:ds | not (isSpace d) 
+                  -> case lext (d:ds) of
+                       e:es -> (w++['.']++e) : es
+                       es -> (w++['.']) : es 
+                '.':[] -> (w++['.']) : []
+                _ -> w : lext cs      
+    [] -> []
+
+unlexTextAGreek :: [String] -> String
+unlexTextAGreek = unlext where
+  unlext s = case s of
+    w:[] -> w
+    w:[c]:[] | isAGreekPunct c -> w ++ [c]
+    w:[c]:cs | isAGreekPunct c -> w ++ [c] ++ " " ++ unlext cs
+    w:ws -> w ++ " " ++ unlext ws
+    [] -> []
+
+isAGreekPunct = flip elem ".,;··"  -- colon: first version · not in charset,
+                                   -- second version · = 00B7 standard code point
+
+-- * Text lexing and unlexing for Ancient Greek: 
+--   1. no capitalization of initial word, 
+--   2. grave/acute accent switch on final syllables of words not followed by punctuation, 
+--   3. accent move from/to support word to/from following clitic words (iterated).
+
+lexAGreek :: String -> [String]
+lexAGreek = fromAGreek . lexTextAGreek
+
+lexAGreek2 :: String -> [String]
+lexAGreek2 = fromAGreek . lexTextAGreek2
+
+unlexAGreek :: [String] -> String
+unlexAGreek = unlexTextAGreek . toAGreek
+
+-- Note: unlexAGreek does not glue punctuation with the previous word, so that short
+-- vowel indication (like a.) differs from sentence end (a .). 
+
+-- | normalize = change grave accent on sentence internal words to acute, 
+-- and shift inherited acutes to the following enclitic (where they are
+-- visible only as shown in the list of enclitics above)
+
+normalize :: String -> String
+normalize = (unlexTextAGreek . fromAGreek . lexTextAGreek) 
+
+fromAGreek :: [String] -> [String]
+fromAGreek s = case s of
+  w:[]:vs -> w:[]:(fromAGreek vs)
+  w:(v:vs) | isAGreekPunct (head v) -> w:v:(fromAGreek vs)
+  w:v:vs | wasEnclitic v && wasEnclitic w ->
+    getEnclitic w : fromAGreek (v:vs)
+  w:v:vs | wasEnclitic v && wasProclitic w ->  -- "ei)' tines*"
+    getProclitic w : getEnclitic v : fromAGreek vs
+  w:v:vs | wasEnclitic v && (hasEndCircum w || 
+    (hasEndAcute w && hasSingleAccent w)) ->  
+    w : getEnclitic v : fromAGreek vs        -- ok "sofoi' tines*"
+  w:v:vs | wasEnclitic v && hasPrefinalAcute w ->
+    w : getEnclitic v : fromAGreek vs
+  w:v:vs | wasEnclitic v && hasEndAcute w ->  -- ok "a)'nvrwpoi' tines*"
+    dropLastAccent w : getEnclitic v : fromAGreek vs
+  w:v:vs | wasEnclitic w ->
+    getEnclitic w : fromAGreek (v:vs)
+  w:ws -> (toAcute w) : (fromAGreek ws)
+  ws -> ws 
+
+-- | de-normalize = change acute accent of end syllables in sentence internal 
+--  (non-enclitic) words to grave accent, and move accents of enclitics to the 
+--  previous word to produce ordinary ancient greek
+
+denormalize :: String -> String
+denormalize = (unlexTextAGreek . toAGreek . lexTextAGreek) 
+
+toAGreek :: [String] -> [String]
+toAGreek s = case s of
+  w:[]:vs -> w:[]:(toAGreek vs)
+  w:v:vs | isAGreekPunct (head v) -> w:[]:v:(toAGreek vs)  -- w:[] for following -to_ancientgreek
+  w:v:vs | isEnclitic v && isEnclitic w -> 
+    addAcute w : toAGreek (dropAccent v:vs)    -- BR 11 Anm.2
+  w:v:vs | isEnclitic v && isProclitic w ->    -- BR 11 a.beta
+    addAcute w: (toAGreek (dropAccent v:vs))
+  w:v:vs | isEnclitic v && (hasEndCircum w || hasEndAcute w) -> 
+    w:(toAGreek (dropAccent v:vs))             -- BR 11 a.alpha,beta
+  w:v:vs | isEnclitic v && hasPrefinalAcute w -> 
+    w:v: toAGreek vs   -- bisyllabic v keeps its accent  BR 11 b.
+  w:v:vs | isEnclitic v -> 
+    (addAcute w):(toAGreek (dropAccent v:vs))  -- BR 11 a.gamma
+  w:v:vs | isEnclitic w -> w:(toAGreek (v:vs))
+  w:ws -> (toGrave w) : (toAGreek ws)
+  ws -> ws 
+
+-- | Change accent on the final syllable of a word
+
+toGrave :: String -> String 
+toGrave = reverse . grave . reverse where
+  grave s = case s of
+    '\'':cs -> '`':cs 
+    c:cs | isAGreekVowel c -> c:cs 
+    c:cs -> c: grave cs
+    _ -> s
+
+toAcute :: String -> String 
+toAcute = reverse . acute . reverse where
+  acute s = case s of
+    '`':cs -> '\'':cs
+    c:cs | isAGreekVowel c -> c:cs 
+    c:cs -> c: acute cs
+    _ -> s
+
+isAGreekVowel = flip elem "aeioyhw"
+
+-- | Accent moves for enclitics and proclitics (atona)
+
+enclitics = [
+  "moy","moi","me",     -- personal pronouns
+  "soy","soi","se",
+  "oy(","oi(","e(",
+  "tis*","ti","tina'",  -- indefinite pronoun 
+  "tino's*","tini'",
+  "tine's*","tina's*",
+  "tinw~n","tisi'","tisi'n",
+  "poy","poi",          -- indefinite adverbs
+  "pove'n","pws*",
+  "ph|","pote'",
+  "ge","te","toi",      -- particles
+  "nyn","per","pw" 
+   -- suffix -"de"
+   -- praes.indik. of fhmi', ei)mi' (except fh's*, ei)~)
+  ] -- and more, BR 11
+
+proclitics = [
+  "o(","h(","oi(","ai(",     -- articles
+  "e)n","ei)s*","e)x","e)k", -- prepositions
+  "ei)","w(s*",              -- conjunctions
+  "oy)","oy)k","oy)c"        -- negation
+  ]
+
+isEnclitic = flip elem enclitics
+isProclitic = flip elem proclitics
+
+-- Check if a word is an enclitic or accented enclitic and extract the enclitic
+
+wasEnclitic = let unaccented = (filter (not . hasAccent) enclitics) 
+                    ++ (map dropAccent (filter hasAccent enclitics))
+                  accented = (filter hasAccent enclitics) 
+                    ++ map addAcute (filter (not . hasAccent) enclitics) 
+              in flip elem (accented ++ unaccented)
+
+wasProclitic = flip elem (map addAcute proclitics)
+
+getEnclitic = 
+  let pairs = zip (enclitics ++ (map dropAccent (filter hasAccent enclitics))
+                   ++ (map addAcute (filter (not . hasAccent) enclitics)))
+                  (enclitics ++ (filter hasAccent enclitics)
+                   ++ (filter (not . hasAccent) enclitics))
+      find = \v -> lookup v pairs
+  in \v -> case (find v) of 
+    Just x -> x 
+    _ -> v
+getProclitic = 
+  let pairs = zip (map addAcute proclitics) proclitics 
+      find = \v -> lookup v pairs
+  in \v -> case (find v) of 
+    Just x -> x 
+    _ -> v
+
+-- | Accent manipulation
+
+dropAccent = reverse . drop . reverse where 
+  drop s = case s of
+    [] -> []
+    '\'':cs -> cs
+    '`':cs -> cs
+    '~':cs -> cs
+    c:cs -> c:drop cs
+
+dropLastAccent = reverse . drop . reverse where 
+  drop s = case s of
+    [] -> []
+    '\'':cs -> cs
+    '`':cs -> cs
+    '~':cs -> cs
+    c:cs -> c:drop cs
+
+addAcute :: String -> String
+addAcute = reverse . acu . reverse where
+  acu w = case w of 
+    c:cs | c == '\'' -> c:cs
+    c:cs | c == '(' -> '\'':c:cs
+    c:cs | c == ')' -> '\'':c:cs
+    c:cs | isAGreekVowel c -> '\'':c:cs
+    c:cs -> c : acu cs
+    _ -> w
+
+-- | Accent checking on end syllables
+
+hasEndAcute = find . reverse where
+  find s = case s of
+    [] -> False
+    '\'':cs -> True
+    '`':cs -> False
+    '~':cs -> False
+    c:cs | isAGreekVowel c -> False
+    _:cs -> find cs
+
+hasEndCircum = find . reverse where
+  find s = case s of
+    [] -> False
+    '\'':cs -> False
+    '`':cs -> False
+    '~':cs -> True
+    c:cs | isAGreekVowel c -> False
+    _:cs -> find cs
+
+hasPrefinalAcute = find . reverse where
+  find s = case s of
+    [] -> False
+    '\'':cs -> False  -- final acute
+    '`':cs -> False
+    '~':cs -> False
+    c:d:cs | isAGreekVowel c && isAGreekVowel d -> findNext cs
+    c:cs | isAGreekVowel c -> findNext cs
+    _:cs -> find cs where
+  findNext s = case s of 
+    [] -> False
+    '\'':cs -> True  -- prefinal acute
+    '`':cs -> False
+    '~':cs -> False
+    c:cs | isAGreekVowel c -> False
+    _:cs -> findNext cs where
+    
+hasSingleAccent v = 
+  hasAccent v && not (hasAccent (dropLastAccent v))
+
+hasAccent v = case v of 
+  [] -> False
+  c:cs -> elem c ['\'','`','~'] || hasAccent cs
+
+{- Tests: 
+
+-- denormalization. Examples in BR 11 work: 
+-}
+enclitics_expls = -- normalized
+  "sofw~n tis*":"sofw~n tine's*":"sof~n tinw~n":  -- a.alpha
+  "sofo's tis*":"sofoi' tine's*":                 -- a.beta
+  "ei) tis*":"ei) tine's*":
+  "a)'nvrwpos* tis*":"a)'nvrwpoi tine's*":        -- a.gamma
+  "doy~los* tis*":"doy~loi tine's*":
+  "lo'gos* tis*":"lo'goi tine's*":"lo'gwn tinw~n":  -- b.
+  "ei) poy tis* tina' i)'doi":                    -- Anm. 2.
+  [] 
+{-
+test = map denormalize enclitics_expls
+
+*PGF.LexingAGreek> test
+  ["sofw~n tis*","sofw~n tines*","sof~n tinwn",
+  "sofo's tis*","sofoi' tines*",
+  "ei)' tis*","ei)' tines*",
+  "a)'nvrwpo's* tis*","a)'nvrwpoi' tines*",
+  "doy~lo's* tis*","doy~loi' tines*",
+  "lo'gos* tis* ","lo'goi tine's*","lo'gwn tinw~n ",
+  "ei)' poy' ti's* tina i)'doi"]
+
+-- normalization:
+
+*PGF.LexingAGreek> map normalize test
+  ["sofw~n tis*","sofw~n tine's*","sof~n tinw~n",
+  "sofo's tis*","sofoi' tine's*",
+  "ei) tis*","ei) tine's*",
+  "a)'nvrwpos* tis*","a)'nvrwpoi tine's*",
+  "doy~los* tis*","doy~loi tine's*",
+  "lo'gos* tis*","lo'goi tine's*","lo'gwn tinw~n",
+  "ei) poy tis* tina' i)'doi"]
+
+*PGF.LexingAGreek> map (normalize . denormalize) enclitics_expls == enclitics_expls
+True
+*PGF.LexingAGreek> map (denormalize . normalize) test == test
+True
+
+-}