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diff --git a/src/GF/CF/Profile.hs b/src/GF/CF/Profile.hs
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+module Profile (postParse) where
+
+import AbsGFC
+import GFC
+import qualified Ident as I
+import CMacros
+---import MMacros
+import CF
+import CFIdent
+import PPrCF -- for error msg
+import PrGrammar
+
+import Operations
+
+import Monad
+import List (nub)
+
+
+-- restoring parse trees for discontinuous constituents, bindings, etc. AR 25/1/2001
+-- revised 8/4/2002 for the new profile structure
+
+postParse :: CFTree -> Err Exp
+postParse tree = do
+ iterm <- errIn "postprocessing initial parse tree" $ tree2term tree
+ return $ term2trm iterm
+
+-- an intermediate data structure
+data ITerm = ITerm (Atom, BindVs) [ITerm] | IMeta deriving (Eq,Show)
+type BindVs = [[I.Ident]]
+
+-- the job is done in two passes:
+-- (1) tree2term: restore constituent order from Profile
+-- (2) term2trm: restore Bindings from Binds
+
+tree2term :: CFTree -> Err ITerm
+tree2term (CFTree (cff@(CFFun (fun,pro)), (_,trees))) = case fun of
+ AM _ -> return IMeta
+ _ -> do
+ args <- mapM mkArg pro
+ binds <- mapM mkBinds pro
+ return $ ITerm (fun, binds) args
+ where
+ mkArg (_,arg) = case arg of
+ [x] -> do -- one occurrence
+ trx <- trees !? x
+ tree2term trx
+ [] -> return IMeta -- suppression
+ _ -> do -- reduplication
+ trees' <- mapM (trees !?) arg
+ xs1 <- mapM tree2term trees'
+ xs2 <- checkArity xs1
+ unif xs2
+
+ checkArity xs = if length (nub [length xx | ITerm _ xx <- xs']) > 1
+ then Bad "arity error"
+ else return xs'
+ where xs' = [t | t@(ITerm _ _) <- xs]
+ unif [] = return $ IMeta
+ unif xs@(ITerm fp@(f,_) xx : ts) = do
+ let hs = [h | ITerm (h,_) _ <- ts]
+ testErr (all (==f) hs) -- if fails, hs must be nonempty
+ ("unification expects" +++ prt f +++ "but found" +++ prt (head hs))
+ xx' <- mapM unifArg [0 .. length xx - 1]
+ return $ ITerm fp xx'
+ where
+ unifArg i = tryUnif [zz !! i | ITerm _ zz <- xs]
+ tryUnif xx = case [t | t@(ITerm _ _) <- xx] of
+ [] -> return IMeta
+ x:xs -> if all (==x) xs
+ then return x
+ else Bad "failed to unify"
+
+ mkBinds (xss,_) = mapM mkBind xss
+ mkBind xs = do
+ ts <- mapM (trees !?) xs
+ let vs = [x | CFTree (CFFun (AV x,_),(_,[])) <- ts]
+ testErr (length ts == length vs) "non-variable in bound position"
+ case vs of
+ [x] -> return x
+ [] -> return $ I.identC "h_" ---- uBoundVar
+ y:ys -> do
+ testErr (all (==y) ys) ("fail to unify bindings of" +++ prt y)
+ return y
+
+term2trm :: ITerm -> Exp
+term2trm IMeta = EAtom (AM 0) ---- mExp0
+term2trm (ITerm (fun, binds) terms) =
+ let bterms = zip binds terms
+ in mkAppAtom fun [mkAbsR xs (term2trm t) | (xs,t) <- bterms]
+
+ --- these are deprecated
+ where
+ mkAbsR c e = foldr EAbs e c
+ mkAppAtom a = mkApp (EAtom a)
+ mkApp = foldl EApp \ No newline at end of file