Current progress

datalog/src/Datalog/Parser.hs

@@ -1,5 +1,4 @@
 {-# LANGUAGE MultilineStrings #-}
-{-# LANGUAGE BlockArguments #-}
 
 module Datalog.Parser (
     parseTerm,
@@ -50,53 +49,32 @@ parseVar = Var () . VarId . T.pack <$> lexeme (liftA2 (:) upperChar (many alphaN
 parseTerm :: Parser Term
 parseTerm = parseVar <|> parseCon
 
-parseAtom :: Parser Atom
+parseAtom :: Parser (Atom' SrcLoc)
-parseAtom = do
+parseAtom = annotateSrcLoc $ do
     rel <- RelId . T.pack <$> lexeme (liftA2 (:) lowerChar (many alphaNumChar))
     args <- parens (parseTerm `sepBy` comma)
     return (Atom () rel args)
 
-parseQuery :: Parser [Atom]
+parseQuery :: Parser [Atom' SrcLoc]
 parseQuery = parseAtom `sepBy` comma
 
-parseFact :: Parser Rule
+parseFact :: Parser (Rule' SrcLoc)
-parseFact = do
+parseFact = annotateSrcLoc $ do
     headAtom <- parseAtom
     period
-    return (Rule () headAtom [])
+    return (Rule NoLoc headAtom [])
 
-parseRule :: Parser Rule
+parseRule :: Parser (Rule' SrcLoc)
 parseRule =
+    annotateSrcLoc $
         try parseFact <|> do
             headAtom <- parseAtom <* symbol ":-"
             bodyAtoms <- parseQuery
             period
-        return (Rule () headAtom bodyAtoms)
+            return (Rule NoLoc headAtom bodyAtoms)
-parseRule' :: Parser (Rule' SrcLoc)
-parseRule' = _
 
--- parseProgram :: Parser Program
 parseProgram :: Parser (Program' SrcLoc)
-parseProgram = do
+parseProgram = annotateSrcLoc $ Program NoLoc <$> many parseRule
-    -- annotateSrcLoc $
-    s <- getSourcePos
-    c <- many parseRule'
-    e <- getSourcePos
-    -- Program _ <$> many parseRule
-    pure $ Program (SrcLoc s e) c
-
-parseProgram' :: Parser (Program' SrcLoc)
-parseProgram' = parseThingWithSub (many parseRule') Program
-
-parseThingWithSub :: (Parser c) -> (SrcLoc -> c -> f SrcLoc) -> Parser (f SrcLoc)
-parseThingWithSub parseSub f = do
-    -- annotateSrcLoc $
-    s <- getSourcePos
-    -- c <- many parseRule'
-    c <- parseSub
-    e <- getSourcePos
-    -- Program _ <$> many parseRule
-    pure $ f (SrcLoc s e) c
 
 annotateSrcLoc :: (Functor f) => Parser (f a) -> Parser (f SrcLoc)
 annotateSrcLoc p = do
@@ -105,10 +83,12 @@ annotateSrcLoc p = do
     f <- getSourcePos
     pure (SrcLoc s f <$ res)
 
-data SrcLoc = SrcLoc
+data SrcLoc
+    = SrcLoc
         { start :: SourcePos
         , end :: SourcePos
         }
+    | NoLoc
     deriving (Show)
 
 test = do

datalog/src/Datalog/Syntax.hs

@@ -3,10 +3,10 @@
 module Datalog.Syntax where
 
 import Data.Char (isUpper)
-import Data.Set (Set)
-import Data.Set qualified as Set
 import Data.Text (Text)
 import Data.Text qualified as T
+import Data.Set qualified as Set
+import Data.Set (Set)
 
 newtype ConId = ConId Text
   deriving (Eq, Ord, Show)
@@ -48,6 +48,16 @@ type Program = Program' ()
 data Program' a = Program a [Rule' a]
   deriving (Eq, Ord, Show)
 
+class Decorable t where
+    decorateNode :: a -> t a -> t a
+
+instance (Decorable Program') where decorateNode x (Program _ rs) = Program x rs
+instance (Decorable Rule') where decorateNode x (Rule _ a as) = Rule x a as
+instance (Decorable Atom') where decorateNode x (Atom _ relId ts) = Atom x relId ts
+instance (Decorable Term') where 
+    decorateNode x (Var _ varId) = Var x varId
+    decorateNode x (Con _ conId) = Con x conId
+
 class HasConstants a where
   constants :: a -> Set ConId
 
@@ -56,7 +66,7 @@ instance HasConstants (Term' a) where
     Con _ x -> Set.singleton x
     Var _ _ -> Set.empty
 
-instance (HasConstants a) => HasConstants [a] where
+instance HasConstants a => HasConstants [a] where
   constants xs = Set.unions (map constants xs)
 
 instance HasConstants (Atom' a) where