very strange behavior (crashes!) with Dynamics
Hal Daume
t-hald at microsoft.com
Thu Aug 14 19:47:28 EDT 2003
Okay, I know I promised that was the last one, but you can actually get
it simpler. Remove all the dynamic map stuff. Just have two files,
Range.hs and Coref.hs, with:
module Range where
import Data.Dynamic
data Range = Single Int
| Range Int Int
deriving (Eq, Ord, Show)
rangeTypeCon = mkTyCon "Range" ; rangeTypeRep = mkAppTy rangeTypeCon []
instance Typeable Range where typeOf _ = rangeTypeRep
{-# NOINLINE rangeTypeCon #-}
{-# NOINLINE rangeTypeRep #-}
rangeDShow :: DShow
rangeDShow = dshowLabel (shows :: Range -> ShowS)
type DShow = Dynamic -> Maybe ShowS
dshowLabel :: Typeable a => (a -> ShowS) -> DShow
dshowLabel x d =
case fromDynamic d of
Nothing -> Nothing
Just v -> Just (shows (typeOf v) . showChar '=' . x v)
and
module Coref where
import Data.Dynamic
import Range
data Coref = Coref Int Int Bool (Maybe String)
deriving (Eq, Ord, Show)
corefTypeCon = mkTyCon "Coref" ; corefTypeRep = mkAppTy corefTypeCon []
instance Typeable Coref where typeOf _ = corefTypeRep
{-# NOINLINE corefTypeCon #-}
{-# NOINLINE corefTypeRep #-}
corefDShow = dshowLabel (shows :: Coref -> ShowS)
now load Coref, do 'Monad.liftM ($"") (corefDShow (toDyn (Range 1 1)))'
which works fine (returns Nothing), then touch it and reload it and do
the same thing and you'll crash.
--
Hal Daume III | hdaume at isi.edu
"Arrest this man, he talks in maths." | www.isi.edu/~hdaume
> -----Original Message-----
> From: glasgow-haskell-bugs-admin at haskell.org
> [mailto:glasgow-haskell-bugs-admin at haskell.org] On Behalf Of Hal Daume
> Sent: Thursday, August 14, 2003 4:06 PM
> To: Hal Daume; glasgow-haskell-bugs at haskell.org
> Subject: RE: very strange behavior (crashes!) with Dynamics
>
>
> Okay, this is the last spam from me.
>
> Here's exactly what you need to do to get the bug.
>
> Create three modules, DynamicMap.hs, Range.hs and Coref.hs, containing
> the following:
>
> ------------ DynamicMap.hs ------------
> module DynamicMap
> ( DynamicMap,
> emptyDM,
> addToDM,
> foldDM
> )
> where
>
> import Data.FiniteMap
> import Data.Dynamic
>
> type DynamicMap = FiniteMap String Dynamic -- cuz TypeRep
> \not \in Ord
> :(
>
> stypeOf x = show (typeOf x)
>
> emptyDM :: DynamicMap
> emptyDM = emptyFM
>
> addToDM :: Typeable a => DynamicMap -> a -> DynamicMap
> addToDM dm a = addToFM dm (stypeOf a) (toDyn a)
>
> foldDM :: (Dynamic -> b -> b) -> b -> DynamicMap -> b
> foldDM f = foldFM (const f)
>
>
> -------------- Range.hs ---------------
> module Range where
>
> import Data.Dynamic
>
> data Range = Single Int
> | Range Int Int
>
> minRange (Single x) = x
> minRange (Range x _) = x
>
> maxRange (Single x) = x
> maxRange (Range _ x) = x
>
> instance Show Range where
> showsPrec _ (Single i) = shows i
> showsPrec _ (Range i j) = shows i . showChar '^' . shows j
>
> instance Eq Range where
> Single i == Single k = i == k
> Single i == Range k l = i == k && k == l
> Range i j == Range k l = i == k && j == l
> Range i j == Single k = i == k && j == k
>
> instance Read Range where
> readsPrec i s
> | '^' `elem` s =
> let n1 = takeWhile (/='^') s
> n2 = drop (length n1+1) s
> in [(Range l h, rest) | (l,[]) <- readsPrec i n1,
> (h,rest) <-
> readsPrec i n2]
> | otherwise = map (\ (a,s) -> (Single a,s)) (readsPrec i s)
>
> instance Ord Range where
> r `compare` s = case minRange r `compare` minRange s of
> EQ -> maxRange r `compare` maxRange s
> x -> x
>
> rangeTypeCon = mkTyCon "Range" ; rangeTypeRep = mkAppTy
> rangeTypeCon []
> instance Typeable Range where typeOf _ = rangeTypeRep
> {-# NOINLINE rangeTypeCon #-}
> {-# NOINLINE rangeTypeRep #-}
>
> rangeDShow :: DShow
> rangeDShow = dshowLabel (shows :: Range -> ShowS)
>
> type DShow = Dynamic -> Maybe ShowS
>
> dshow0 :: DShow
> dshow0 = const Nothing
>
> dshowLabel :: Typeable a => (a -> ShowS) -> DShow
> dshowLabel x d =
> case fromDynamic d of
> Nothing -> Nothing
> Just v -> Just (shows (typeOf v) . showChar '=' . x v)
>
>
> -------------- Coref.hs ---------------
> module Coref where
>
> import DynamicMap
> import Data.Dynamic
> import Range
>
> data Coref = Coref Int Int Bool (Maybe String)
> deriving (Eq, Ord, Show)
>
> corefTypeCon = mkTyCon "Coref" ; corefTypeRep = mkAppTy
> corefTypeCon []
> instance Typeable Coref where typeOf _ = corefTypeRep
> {-# NOINLINE corefTypeCon #-}
> {-# NOINLINE corefTypeRep #-}
>
> corefDShow = dshowLabel (shows :: Coref -> ShowS)
>
>
> showDM :: DShow -> DynamicMap -> ShowS
> showDM sd = foldDM (\d b -> case sd d of { Nothing -> b ;
> Just s -> s .
> b }) id
>
> dm1 = addToDM emptyDM (Range 1 2)
> ---------------------------------------
>
> Now, load Coref.hs in GHCi:
>
> ___ ___ _
> / _ \ /\ /\/ __(_)
> / /_\// /_/ / / | | GHC Interactive, version 6.0, for
> Haskell 98.
> / /_\\/ __ / /___| | http://www.haskell.org/ghc/
> \____/\/ /_/\____/|_| Type :? for help.
>
> Loading package base ... linking ... done.
> Loading package lang ... linking ... done.
> Prelude> :load c:/home/t-hald/projects/Bugs/Coref.hs
> Compiling DynamicMap ( DynamicMap.hs, interpreted )
> Compiling Range ( Range.hs, interpreted )
> Compiling Coref ( c:/home/t-hald/projects/Bugs/Coref.hs,
> interpreted )
> Ok, modules loaded: Coref, Range, DynamicMap.
> *Coref> showDM corefDShow dm1 ""
> ""
> *Coref> :!touch Coref.hs
> *Coref> :r
> Compiling Coref ( c:/home/t-hald/projects/Bugs/Coref.hs,
> interpreted )
> Ok, modules loaded: Coref, Range, DynamicMap.
> *Coref> showDM corefDShow dm1 ""
> "Coref=Coref 1 2
> Process ghci exited abnormally with code 5
>
>
> for some reason having the DShow definitions in the same file as Range
> is important (I originally tried having the DShow definitions in their
> own file, imported by all the others, but that didn't exhibit
> the bug).
>
>
> --
> Hal Daume III | hdaume at isi.edu
> "Arrest this man, he talks in maths." | www.isi.edu/~hdaume
>
>
> > -----Original Message-----
> > From: glasgow-haskell-bugs-admin at haskell.org
> > [mailto:glasgow-haskell-bugs-admin at haskell.org] On Behalf
> Of Hal Daume
> > Sent: Thursday, August 14, 2003 3:46 PM
> > To: Hal Daume; glasgow-haskell-bugs at haskell.org
> > Subject: RE: very strange behavior (crashes!) with Dynamics
> >
> >
> > This hasn't yet been posted, but I've actually whittled it
> > down quite a
> > bit.
> >
> > All we need is to import the Util.DynamicMap and do:
> >
> > > dm1 = addToDM emptyDM (Range 1 2)
> > > showDM :: DShow -> DynamicMap -> ShowS
> > > showDM sd = foldDM (\d b -> case sd d of { Nothing -> b ;
> > Just s -> s
> > . b }) id
> >
> > and do the show definition for Coref and then we get:
> >
> > Compiling ReadCorefData (
> > c:/home/t-hald/projects/PennUtil/ReadCorefData.hs, interpreted )
> > Ok, modules loaded: ReadCorefData, PennUtil.Util, Util.DynamicMap,
> > NLP.PennParser, NLP.FiniteMap, NLP.String, NLP.Util, Common.
> > *ReadCorefData> showDM corefDShow dm1 ""
> > Loading package haskell98 ... linking ... done.
> > ""
> > *ReadCorefData> :!touch ReadCorefData.hs
> > *ReadCorefData> :r
> > Compiling ReadCorefData (
> > c:/home/t-hald/projects/PennUtil/ReadCorefData.hs, interpreted )
> > Ok, modules loaded: ReadCorefData, PennUtil.Util, Util.DynamicMap,
> > NLP.PennParser, NLP.FiniteMap, NLP.String, NLP.Util, Common.
> > *ReadCorefData> showDM corefDShow dm1 ""
> > "Coref=Coref 1 2
> > Process ghci exited abnormally with code 5
> >
> >
> > interestingly it seems to be trying to read this as the range
> > (since the
> > two ints are the same as the initial ones)...
> >
> > --
> > Hal Daume III | hdaume at isi.edu
> > "Arrest this man, he talks in maths." |
> www.isi.edu/~hdaume
> >
> >
> > > -----Original Message-----
> > > From: Hal Daume
> > > Sent: Thursday, August 14, 2003 12:37 PM
> > > To: 'glasgow-haskell-bugs at haskell.org'
> > > Subject: very strange behavior (crashes!) with Dynamics
> > >
> > >
> > > First, I apologize for the length of this message.
> > > Unfortunately, I cannot whittle this down to a smaller example.
> > >
> > > I'm dealing with parse trees, whose datatype looks like:
> > >
> > > > data AnnTree a
> > > > = Term { treeTag :: PackedString, treeText ::
> > > PackedString , treeAnn :: a }
> > > > | NonTerm { treeTag :: PackedString, treeChildren ::
> > > [AnnTree a], treeAnn :: a }
> > > > deriving (Eq, Ord)
> > >
> > > In particular, I parameterize these over a DynamicMap
> > > datatype, which looks like:
> > >
> > > > import Data.Dynamic
> > > > type DynamicMap = FiniteMap String Dynamic -- cuz TypeRep
> > > \not \in Ord :(
> > >
> > > This supports, for instance:
> > >
> > > > stypeOf x = show (typeOf x)
> > > > ttypeOf (x :: T a) = stypeOf (undefined :: a)
> > > >
> > > > emptyDM :: DynamicMap
> > > > emptyDM = emptyFM
> > > >
> > > > addToDM :: Typeable a => DynamicMap -> a -> DynamicMap
> > > > addToDM dm a = addToFM dm (stypeOf a) (toDyn a)
> > > >
> > > > lookupDM :: Typeable a => DynamicMap -> Maybe a
> > > > lookupDM dm :: Maybe a =
> > > > case lookupFM dm (stypeOf (undefined :: a)) of
> > > > Nothing -> Nothing
> > > > Just x -> fromDynamic x
> > >
> > > as well as a few other of the standard FM functions that I need.
> > >
> > > I have a type synonym:
> > >
> > > > type DTree = AnnTree DynamicMap
> > >
> > > so that I can add whatever types of annotations I want to
> the tree.
> > >
> > > I also provide methods of showing the trees with various
> > > annotations shown, based on a DShow type:
> > >
> > > > type DShow = Dynamic -> Maybe ShowS
> > > > dshowLabel :: Typeable a => (a -> ShowS) -> DShow
> > > > dshowLabel x d =
> > > > case fromDynamic d of
> > > > Nothing -> Nothing
> > > > Just v -> Just (shows (typeOf v) . showChar '=' . x v)
> > > >
> > > > showDTreeWith :: DShow -> DTree -> ShowS
> > > > showDTreeWith shws t =
> > > > showChar '(' .
> > > > showString (unpackPS (treeTag t)) .
> > > > showChar ' ' . showAnn (treeAnn t) .
> > > > (if isTerm t
> > > > then showString (unpackPS (treeText t))
> > > > else showChildren (treeChildren t)) .
> > > > showChar ')'
> > > > where
> > > > showChildren [] = showString "<<EMPTY>>"
> > > > showChildren [ch] = showDTreeWith shws ch
> > > > showChildren (ch:chl) = showDTreeWith shws ch .
> > > showChar ' ' . showChildren chl
> > > > showAnn a = showList (foldDM showAnn' [] a)
> > > > showAnn' dyn acc =
> > > > case shws dyn of
> > > > Nothing -> acc
> > > > Just ss -> showChar '{' . ss . showChar '}' : acc
> > > > showList [] = id
> > > > showList [x] = showChar '{' . x . showChar '}' .
> showChar ' '
> > > > showList (x:xs) = showChar '{' . x . showList' xs .
> > > showChar '}' . showChar ' '
> > > > showList' [] = id
> > > > showList' (x:xs) = showChar ';' . x . showList' xs
> > >
> > > Basically, what this does is it is given a DShow (which can
> > > be combined, of course, using non-shown functions), and
> > > prints the tree with the dynamic annotations shown in braces.
> > > The dshowLabel function takes a shows function and creates a
> > > DShow function based on it.
> > >
> > > For instance, I have a coreference data type, which looks like:
> > >
> > > > data Coref = Coref Int Int Bool (Maybe String)
> > > > -- Id, ref, in-min; eventually we cannonicalize these
> > > > -- and we can assume id= ref, type
> > > > deriving (Eq, Ord, Show)
> > >
> > > We make this an instance of Typeable so we can put it in
> > dynamic maps:
> > >
> > > > corefTypeCon = mkTyCon "Coref" ; corefTypeRep = mkAppTy
> > > corefTypeCon []
> > > > instance Typeable Coref where typeOf _ = corefTypeRep
> > > > {-# NOINLINE corefTypeCon #-}
> > > > {-# NOINLINE corefTypeRep #-}
> > >
> > > Now, we have another annotation type, Range, which specifies
> > > what subset of the sentence a given node covers.
> > >
> > > > data Range = Single Int
> > > > | Range Int Int
> > > >
> > > > instance Show Range where
> > > > showsPrec _ (Single i) = shows i
> > > > showsPrec _ (Range i j) = shows i . showChar '^' . shows j
> > > >
> > > > rangeTypeCon = mkTyCon "Range" ; rangeTypeRep = mkAppTy
> > > rangeTypeCon []
> > > > instance Typeable Range where typeOf _ = rangeTypeRep
> > > > {-# NOINLINE rangeTypeCon #-}
> > > > {-# NOINLINE rangeTypeRep #-}
> > >
> > > And we can take a DTree and add ranges with:
> > >
> > > > numberTree :: Int -> DTree -> (Int, DTree)
> > > > numberTree n t@(Term _ _ _) = (n+1, addAnn t (Single n))
> > > > numberTree n t@(NonTerm _ chl _) =
> > > > let (n',chl') = mapAccumL numberTree n chl
> > > > in (n', addAnn (t { treeChildren = chl' }) (mkRange
> > n (n'-1)))
> > >
> > > The associate DShow function is:
> > >
> > > > rangeDShow :: DShow
> > > > rangeDShow = dshowLabel (shows :: Range -> ShowS)
> > >
> > > Now, we parse a tree, convert it into a dtree and number it:
> > >
> > > We do:
> > >
> > > > (_:Right (_,tree):_) = parseFile "wsj93_005.0011.par"
> > > (unsafePerformIO $ readFile "wsj93_005.0011.par")
> > >
> > > now, tree is of type AnnTree (). We can convert this to a
> > > DTree with nothing in it by applying the mkDTree function:
> > >
> > > > mkDTree :: Tree -> DTree
> > > > mkDTree (Term tag txt _) = Term tag txt emptyDM
> > > > mkDTree (NonTerm tag chl _) = NonTerm tag (map mkDTree
> > chl) emptyDM
> > >
> > > And the number it, by doing:
> > >
> > > > pTree :: DTree
> > > > pTree = snd $ numberTree 1 $ mkDTree tree
> > >
> > > we can test showing this by:
> > >
> > > *ReadCorefData> showDTreeWith rangeDShow pTree ""
> > > "(TOP {{Range=1^32}} (S {{Range=1^32}} (NP-A {{Range=1^11}}
> > > (NPB {{Range=1^4}} (NE {{Range=1^3}} (NNP {{Range=1}}
> > > Michael) (NNP {{Range=2}} D.) (NNP {{Range=3}} Casey)) (COMMA
> > > {{Range=4}} ,)) (NP {{Range=5^11}} (NPB {{Range=5^11}} (DT
> > > {{Range=5}} a) (JJ {{Range=6}} top) (NE {{Range=7}} (NNP
> > > {{Range=7}} Johnson)) (CC {{Range=8}} &) (NE {{Range=9}} (NNP
> > > {{Range=9}} Johnson)) (NN {{Range=10}} manager) (COMMA
> > > {{Range=11}} ,)))) (VP {{Range=12^32}} (VBD {{Range=12}}
> > > moved) (PP {{Range=13^23}} (TO {{Range=13}} to) (NP-A
> > > {{Range=14^23}} (NPB {{Range=14^17}} (NE {{Range=14^16}} (NNP
> > > {{Range=14}} Genetic) (NNP {{Range=15}} Therapy) (NNP
> > > {{Range=16}} Inc.)) (COMMA {{Range=17}} ,)) (NP
> > > {{Range=18^23}} (NPB {{Range=18^21}} (DT {{Range=18}} a) (JJ
> > > {{Range=19}} small) (NN {{Range=20}} biotechnology) (NN
> > > {{Range=21}} concern)) (ADVP {{Range=22^23}} (RB {{Range=22}}
> > > here) (COMMA {{Range=23}} ,))))) (SG {{Range=24^32}} (VP
> > > {{Range=24^32}} (TO {{Range=24}} to) (VP-A {{Range=25^32}}
> > > (VB {{Range=25}} become) (NP-A_AND {{Range=26^32}} (NP
> > > {{Range=26^27}} (NPB {{Range=26^27}} (PRP$ {{Range=26}} its)
> > > (NN {{Range=27}} president))) (CC {{Range=28}} and) (NP
> > > {{Range=29^32}} (NPB {{Range=29^32}} (NN {{Range=29}} chief)
> > > (VBG {{Range=30}} operating) (NN {{Range=31}} officer)
> > > (PERIOD {{Range=32}} .))))))))))"
> > >
> > > you can take my word that this is correct :).
> > >
> > > We can show it without the annotations by:
> > >
> > > *ReadCorefData> showDTreeWith dshow0 pTree ""
> > > "(TOP (S (NP-A (NPB (NE (NNP Michael) (NNP D.) (NNP Casey))
> > > (COMMA ,)) (NP (NPB (DT a) (JJ top) (NE (NNP Johnson)) (CC &)
> > > (NE (NNP Johnson)) (NN manager) (COMMA ,)))) (VP (VBD moved)
> > > (PP (TO to) (NP-A (NPB (NE (NNP Genetic) (NNP Therapy) (NNP
> > > Inc.)) (COMMA ,)) (NP (NPB (DT a) (JJ small) (NN
> > > biotechnology) (NN concern)) (ADVP (RB here) (COMMA ,)))))
> > > (SG (VP (TO to) (VP-A (VB become) (NP-A_AND (NP (NPB (PRP$
> > > its) (NN president))) (CC and) (NP (NPB (NN chief) (VBG
> > > operating) (NN officer) (PERIOD .))))))))))"
> > >
> > > now, note that we have *NOT* ever added any annotations
> > > having to do with corefs to it.
> > >
> > > however, we can still segfault ghci by doing:
> > >
> > > *ReadCorefData> showDTreeWith corefDShow pTree ""
> > > "(TOP {{Coref=Coref 1 32
> > > Process ghci exited abnormally with code 5
> > >
> > > where it gets the 1 32 is beyond me :).
> > >
> > > now, for some more fun, I can reload this module into ghci,
> > > and run it and it works fine:
> > >
> > > ___ ___ _
> > > / _ \ /\ /\/ __(_)
> > > / /_\// /_/ / / | | GHC Interactive, version 6.0, for
> > > Haskell 98.
> > > / /_\\/ __ / /___| | http://www.haskell.org/ghc/
> > > \____/\/ /_/\____/|_| Type :? for help.
> > >
> > > Loading package base ... linking ... done.
> > > Loading package lang ... linking ... done.
> > > : Can't find module `'
> > > (use -v to see a list of the files searched for)
> > > Prelude> :load c:/home/t-hald/projects/PennUtil/ReadCorefData.hs
> > > Skipping Common ( /home/t-hald/projects/Common.hs,
> > > /home/t-hald/projects/Common.o )
> > > Compiling NLP.Util (
> > > /home/t-hald/projects/NLP/Util.hs, interpreted )
> > > Skipping NLP.String (
> > > /home/t-hald/projects/NLP/String.lhs,
> > > /home/t-hald/projects/NLP/String.o )
> > > Skipping NLP.FiniteMap (
> > > /home/t-hald/projects/NLP/FiniteMap.hs,
> > > /home/t-hald/projects/NLP/FiniteMap.o )
> > > Compiling NLP.PennParser (
> > > /home/t-hald/projects/NLP/PennParser.hs, interpreted )
> > > Compiling Util.DynamicMap (
> > > /home/t-hald/projects/Util/DynamicMap.hs, interpreted )
> > > Compiling PennUtil.Util (
> > > /home/t-hald/projects/PennUtil/Util.hs, interpreted )
> > > Compiling ReadCorefData (
> > > c:/home/t-hald/projects/PennUtil/ReadCorefData.hs, interpreted )
> > > Ok, modules loaded: ReadCorefData, PennUtil.Util,
> > > Util.DynamicMap, NLP.PennParser, NLP.FiniteMap, NLP.String,
> > > NLP.Util, Common.
> > > *ReadCorefData> showDTreeWith corefDShow pTree ""
> > > Loading package haskell98 ... linking ... done.
> > > "(TOP (S (NP-A (NPB (NE (NNP Michael) (NNP D.) (NNP Casey))
> > > (COMMA ,)) (NP (NPB (DT a) (JJ top) (NE (NNP Johnson)) (CC &)
> > > (NE (NNP Johnson)) (NN manager) (COMMA ,)))) (VP (VBD moved)
> > > (PP (TO to) (NP-A (NPB (NE (NNP Genetic) (NNP Therapy) (NNP
> > > Inc.)) (COMMA ,)) (NP (NPB (DT a) (JJ small) (NN
> > > biotechnology) (NN concern)) (ADVP (RB here) (COMMA ,)))))
> > > (SG (VP (TO to) (VP-A (VB become) (NP-A_AND (NP (NPB (PRP$
> > > its) (NN president))) (CC and) (NP (NPB (NN chief) (VBG
> > > operating) (NN officer) (PERIOD .))))))))))"
> > > *ReadCorefData>
> > >
> > > just as it shouldn't print any coref data (as it doesn't know
> > > any!), it doesn't.
> > >
> > > now, i insert a blank line somewhere in the source, save it,
> > > and reload (just to force ghci to actually reload it), and:
> > >
> > > *ReadCorefData> :r
> > > Compiling ReadCorefData (
> > > c:/home/t-hald/projects/PennUtil/ReadCorefData.hs, interpreted )
> > > Ok, modules loaded: ReadCorefData, PennUtil.Util,
> > > Util.DynamicMap, NLP.PennParser, NLP.FiniteMap, NLP.String,
> > > NLP.Util, Common.
> > > *ReadCorefData> showDTreeWith corefDShow pTree ""
> > > "(TOP {{Coref=Coref 1 32
> > > Process ghci exited abnormally with code 5
> > >
> > >
> > > I can do this every time :).
> > >
> > > I should mention that NLP.FiniteMap was created by stealing
> > > the code from Data.FiniteMap and adding a few functions I
> > > felt were missing.
> > >
> > > I've attached all the relevant source code. The
> > > PennUtil/ReadCorefData.hs is the module we're trying to run.
> > > You should untar it into a new directory if you want to
> > > experiment with it.
> > >
> > > Any help would really be incredibly appreciated.
> > >
> > > Thanks!
> > >
> > > - Hal
> > >
> > > --
> > > Hal Daume III | hdaume at isi.edu
> > > "Arrest this man, he talks in maths." |
> www.isi.edu/~hdaume
> >
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