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gf-core/src/compiler/GF/Compile/Compute/ConcreteNew.hs
hallgren ab97deae57 Compute.ConcreteNew: add missing case for variant functions
Also adding a test case in the test suite for this.
2012-12-10 13:25:32 +00:00

350 lines
12 KiB
Haskell

-- | Functions for computing the values of terms in the concrete syntax, in
-- | preparation for PMCFG generation.
module GF.Compile.Compute.ConcreteNew
( normalForm
, Value(..), Env, eval, apply, value2term
) where
import GF.Grammar hiding (Env, VGen, VApp, VRecType)
import GF.Grammar.Lookup(lookupResDef,allParamValues)
import GF.Grammar.Predef(cPredef,cErrorType,cTok,cStr)
import GF.Grammar.PatternMatch(matchPattern)
import GF.Grammar.Lockfield(unlockRecord,lockLabel,isLockLabel)
import GF.Compile.Compute.Value
import GF.Compile.Compute.Predef(predefs)
import GF.Data.Str(Str,glueStr,str2strings,str,sstr,plusStr,strTok)
import GF.Data.Operations(Err,err,maybeErr,combinations)
import GF.Data.Utilities(mapSnd,mapBoth,apBoth,apSnd)
import Control.Monad(liftM,liftM2,mplus)
import Data.List (findIndex,intersect,isInfixOf,nub)
import Data.Char (isUpper,toUpper,toLower)
import Text.PrettyPrint
import qualified Data.ByteString.Char8 as BS
import qualified Data.Map as Map
import Debug.Trace(trace)
-- * Main entry points
normalForm :: SourceGrammar -> Term -> Term
normalForm gr = nfx gr []
nfx gr env = value2term gr [] . eval gr env
eval :: SourceGrammar -> Env -> Term -> Value
eval gr env t = value (gr,env) t
apply gr env = apply' (gr,env)
--------------------------------------------------------------------------------
-- * Environments
type CompleteEnv = (SourceGrammar,Env)
ext b (gr,env) = (gr,b:env)
var env x = maybe unbound id (lookup x (snd env))
where unbound = bug ("Unknown variable: "++showIdent x)
-- * Computing values
-- | Computing the value of a top-level term
value0 gr t = eval gr [] t
-- | Computing the value of a term
value :: CompleteEnv -> Term -> Value
value env t0 =
case t0 of
Vr x -> var env x
Q x@(m,f)
| m == cPredef -> if f==cErrorType -- to be removed
then let p = identC (BS.pack "P")
in value0 (fst env) (mkProd [(Implicit,p,typeType)] (Vr p) [])
else VApp x []
| otherwise -> valueResDef (fst env) x
QC x -> VCApp x []
App e1 e2 -> apply' env e1 [value env e2]
Let (x,(oty,t)) body -> value (ext (x,value env t) env) body
Meta i -> VMeta i (snd env) []
Prod bt x t1 t2 -> VProd bt (value env t1) x (Bind $ \ vx -> value (ext (x,vx) env) t2)
Abs bt x t -> VAbs bt x (Bind $ \ vx -> value (ext (x,vx) env) t)
EInt n -> VInt n
EFloat f -> VFloat f
K s -> VString s
Empty -> VString ""
Sort s | s == cTok -> VSort cStr -- to be removed
| otherwise -> VSort s
ImplArg t -> VImplArg (value env t)
Table p res -> VTblType (value env p) (value env res)
RecType rs -> VRecType [(l,value env ty) | (l,ty) <- rs]
t@(ExtR t1 t2) -> extR t (both (value env) (t1,t2))
FV ts -> vfv (map (value env) ts)
R as -> VRec [(lbl,value env t)|(lbl,(oty,t))<-as]
T i cs -> valueTable env i cs
V ty ts -> VV ty (map (value env) ts)
C t1 t2 -> vconcat (both (value env) (t1,t2))
S t1 t2 -> select (fst env) (both (value env) (t1,t2))
P t l -> --maybe (bug $ "project "++show l++" from "++show v) id $
maybe (VP v l) id $
proj l v where v = (value env t)
Alts t tts -> VAlts (value env t) (mapBoth (value env) tts)
Strs ts -> VStrs (map (value env) ts)
Glue t1 t2 -> glue (both (value env) (t1,t2))
ELin c r -> unlockVRec c (value env r)
EPatt p -> VPatt p -- hmm
t -> ppbug (text "value"<+>ppTerm Unqualified 10 t $$ text (show t))
valueResDef gr = err bug (value0 gr) . lookupResDef gr
vconcat vv@(v1,v2) =
case vv of
(VError _,_) -> v1
(VString "",_) -> v2
(_,VError _) -> v2
(_,VString "") -> v1
_ -> VC v1 v2
proj l v | isLockLabel l = return (VRec [])
---- a workaround 18/2/2005: take this away and find the reason
---- why earlier compilation destroys the lock field
proj l v =
case v of
VFV vs -> liftM vfv (mapM (proj l) vs)
VRec rs -> lookup l rs
VExtR v1 v2 -> proj l v2 `mplus` proj l v1 -- hmm
_ -> return (ok1 VP v l)
ok1 f v1@(VError {}) _ = v1
ok1 f v1 v2 = f v1 v2
ok2 f v1@(VError {}) _ = v1
ok2 f _ v2@(VError {}) = v2
ok2 f v1 v2 = f v1 v2
unlockVRec ::Ident -> Value -> Value
unlockVRec c v =
case v of
-- VClosure env t -> err bug (VClosure env) (unlockRecord c t)
VAbs bt x (Bind f) -> VAbs bt x (Bind $ \ v -> unlockVRec c (f v))
VRec rs -> plusVRec rs lock
_ -> VExtR v (VRec lock) -- hmm
-- _ -> bug $ "unlock non-record "++show v
where
lock = [(lockLabel c,VRec [])]
-- suspicious, but backwards compatible
plusVRec rs1 rs2 = VRec ([(l,v)|(l,v)<-rs1,l `notElem` ls2] ++ rs2)
where ls2 = map fst rs2
extR t vv =
case vv of
(VFV vs,v2) -> vfv [extR t (v1,v2)|v1<-vs]
(v1,VFV vs) -> vfv [extR t (v1,v2)|v2<-vs]
(VRecType rs1, VRecType rs2) ->
case intersect (map fst rs1) (map fst rs2) of
[] -> VRecType (rs1 ++ rs2)
ls -> error $ text "clash"<+>text (show ls)
(VRec rs1, VRec rs2) -> plusVRec rs1 rs2
(v1 , VRec [(l,_)]) | isLockLabel l -> v1 -- hmm
(VS (VV t vs) s,v2) -> VS (VV t [extR t (v1,v2)|v1<-vs]) s
(v1,v2) -> ok2 VExtR v1 v2 -- hmm
-- (v1,v2) -> error $ text "not records" $$ text (show v1) $$ text (show v2)
where
error explain = ppbug $ text "The term" <+> ppTerm Unqualified 0 t
<+> text "is not reducible" $$ explain
glue vv = case vv of
(VFV vs,v2) -> vfv [glue (v1,v2)|v1<-vs]
(v1,VFV vs) -> vfv [glue (v1,v2)|v2<-vs]
(VString s1,VString s2) -> VString (s1++s2)
(v1,VAlts d vs) -> VAlts (glx d) [(glx v,c) | (v,c) <- vs]
where glx v2 = glue (v1,v2)
(v1@(VAlts {}),v2) ->
--err (const (ok2 VGlue v1 v2)) id $
err bug id $
do y' <- strsFromValue v2
x' <- strsFromValue v1
return $ vfv [foldr1 VC (map VString (str2strings (glueStr v u))) | v <- x', u <- y']
(VC va vb,v2) -> VC va (glue (vb,v2))
(v1,VC va vb) -> VC (glue (va,va)) vb
(VS (VV ty vs) vb,v2) -> VS (VV ty [glue (v,v2)|v<-vs]) vb
(v1,VS (VV ty vs) vb) -> VS (VV ty [glue (v1,v)|v<-vs]) vb
-- (v1,v2) -> ok2 VGlue v1 v2
(v1,v2) -> bug vv
where
bug vv = ppbug $ text "glue"<+>text (show vv)
-- | to get a string from a value that represents a sequence of terminals
strsFromValue :: Value -> Err [Str]
strsFromValue t = case t of
VString s -> return [str s]
VC s t -> do
s' <- strsFromValue s
t' <- strsFromValue t
return [plusStr x y | x <- s', y <- t']
{-
VGlue s t -> do
s' <- strsFromValue s
t' <- strsFromValue t
return [glueStr x y | x <- s', y <- t']
-}
VAlts d vs -> do
d0 <- strsFromValue d
v0 <- mapM (strsFromValue . fst) vs
c0 <- mapM (strsFromValue . snd) vs
let vs' = zip v0 c0
return [strTok (str2strings def) vars |
def <- d0,
vars <- [[(str2strings v, map sstr c) | (v,c) <- zip vv c0] |
vv <- combinations v0]
]
VFV ts -> mapM strsFromValue ts >>= return . concat
VStrs ts -> mapM strsFromValue ts >>= return . concat
_ -> fail "cannot get Str from value"
vfv vs = case nub vs of
[v] -> v
vs -> VFV vs
select gr vv =
case vv of
(v1,VFV vs) -> vfv [select gr (v1,v2)|v2<-vs]
(VFV vs,v2) -> vfv [select gr (v1,v2)|v1<-vs]
(v1@(VV pty rs),v2) ->
err (const (VS v1 v2)) id $
do ats <- allParamValues gr pty
let vs = map (value0 gr) ats
i <- maybeErr "no match" $ findIndex (==v2) vs
return (rs!!i)
(v1@(VT i cs),v2) ->
err bug (valueMatch gr) $ matchPattern cs (value2term gr [] v2)
(VS (VV pty rs) v12,v2) -> VS (VV pty [select gr (v11,v2)|v11<-rs]) v12
(v1,v2) -> ok2 VS v1 v2
valueMatch gr (Bind f,env') = f (mapSnd (value0 gr) env')
valueTable env@(gr,bs) i cs =
case i of
TComp ty -> VV ty (map (value env.snd) cs)
_ -> err keep id convert
where
keep _ = VT i (err bug id $ mapM valueCase cs)
valueCase (p,t) = do p' <- inlinePattMacro p
return (p',Bind $ \ bs' -> value (gr,bs'++bs) t)
convert = do ty <- getTableType i
let pty = nfx gr bs ty
vs <- allParamValues gr pty
cs' <- mapM valueCase cs
sts <- mapM (matchPattern cs') vs
return $ VV pty (map (valueMatch gr) sts)
inlinePattMacro p =
case p of
PM qc -> case valueResDef gr qc of
VPatt p' -> inlinePattMacro p'
r -> ppbug $ hang (text "Expected pattern macro:") 4
(text (show r))
_ -> composPattOp inlinePattMacro p
apply' env t [] = value env t
apply' env t vs =
case t of
QC x -> VCApp x vs
Q x@(m,f) | m==cPredef -> let constr = --trace ("predef "++show x) .
VApp x
in maybe constr id (Map.lookup f predefs) vs
| otherwise -> err bug (\t->apply' (fst env,[]) t vs)
(lookupResDef (fst env) x)
App t1 t2 -> apply' env t1 (value env t2 : vs)
-- Abs b x t -> beta env b x t vs
_ -> vapply (value env t) vs
vapply v [] = v
vapply v vs =
case v of
VError {} -> v
-- VClosure env (Abs b x t) -> beta gr env b x t vs
VAbs bt _ (Bind f) -> vbeta bt f vs
VS (VV t fs) s -> VS (VV t [vapply f vs|f<-fs]) s
VFV fs -> vfv [vapply f vs|f<-fs]
v -> bug $ "vapply "++show v++" "++show vs
vbeta bt f (v:vs) =
case (bt,v) of
(Implicit,VImplArg v) -> ap v
(Explicit, v) -> ap v
where
ap (VFV avs) = vfv [vapply (f v) vs|v<-avs]
ap v = vapply (f v) vs
{-
beta env b x t (v:vs) =
case (b,v) of
(Implicit,VImplArg v) -> apply' (ext (x,v) env) t vs
(Explicit, v) -> apply' (ext (x,v) env) t vs
-}
-- tr s f vs = trace (s++" "++show vs++" = "++show r) r where r = f vs
-- | Convert a value back to a term
value2term :: SourceGrammar -> [Ident] -> Value -> Term
value2term gr xs v0 =
case v0 of
VApp f vs -> foldl App (Q f) (map v2t vs)
VCApp f vs -> foldl App (QC f) (map v2t vs)
VGen j vs -> foldl App (Vr (reverse xs !! j)) (map v2t vs)
VMeta j env vs -> foldl App (Meta j) (map v2t vs)
-- VClosure env (Prod bt x t1 t2) -> Prod bt x (v2t (eval gr env t1))
-- (nf gr (push x (env,xs)) t2)
-- VClosure env (Abs bt x t) -> Abs bt x (nf gr (push x (env,xs)) t)
VProd bt v x (Bind f) -> Prod bt x (v2t v) (v2t' x f)
VAbs bt x (Bind f) -> Abs bt x (v2t' x f)
VInt n -> EInt n
VFloat f -> EFloat f
VString s -> if null s then Empty else K s
VSort s -> Sort s
VImplArg v -> ImplArg (v2t v)
VTblType p res -> Table (v2t p) (v2t res)
VRecType rs -> RecType [(l,v2t v) | (l,v) <- rs]
VRec as -> R [(l,(Nothing,v2t v))|(l,v) <- as]
VV t vs -> V t (map v2t vs)
VT i cs -> T i (map nfcase cs)
VFV vs -> FV (map v2t vs)
VC v1 v2 -> C (v2t v1) (v2t v2)
VS v1 v2 -> S (v2t v1) (v2t v2)
VP v l -> P (v2t v) l
VAlts v vvs -> Alts (v2t v) (mapBoth v2t vvs)
VStrs vs -> Strs (map v2t vs)
-- VGlue v1 v2 -> Glue (v2t v1) (v2t v2)
VExtR v1 v2 -> ExtR (v2t v1) (v2t v2)
VError err -> Error err
_ -> bug ("value2term "++show v0)
where
v2t = value2term gr xs
v2t' x f = value2term gr (x:xs) (f (gen xs))
pushs xs e = foldr push e xs
push x (env,xs) = ((x,gen xs):env,x:xs)
gen xs = VGen (length xs) []
nfcase (p,Bind f) = (p,value2term gr xs' (f env'))
where (env',xs') = pushs (pattVars p) ([],xs)
-- nf gr (env,xs) = value2term gr xs . eval gr env
pattVars = nub . pv
where
pv p = case p of
PV i -> [i]
PAs i p -> i:pv p
_ -> collectPattOp pv p
---
both = apBoth
bug msg = ppbug (text msg)
ppbug doc = error $ render $
hang (text "Internal error in Compute.ConcreteNew:") 4 doc