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-rw-r--r--src/Parser/Expr.hs320
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diff --git a/src/Parser/Expr.hs b/src/Parser/Expr.hs
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+++ b/src/Parser/Expr.hs
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+module Parser.Expr (
+ procName,
+
+ varName,
+ newVarName,
+ addVarName,
+
+ someExpr,
+ typedExpr,
+) where
+
+import Control.Applicative (liftA2)
+import Control.Monad.Combinators.Expr
+import Control.Monad.Identity
+import Control.Monad.State
+
+import Data.Char
+import Data.Maybe
+import Data.Scientific
+import qualified Data.Set as S
+import Data.Text (Text)
+import Data.Text qualified as T
+import qualified Data.Text.Lazy as TL
+import Data.Typeable
+import Data.Void
+
+import Text.Megaparsec hiding (State)
+import Text.Megaparsec.Char
+import qualified Text.Megaparsec.Char.Lexer as L
+
+import Parser.Core
+import Process (ProcName(..))
+import Test
+
+procName :: TestParser ProcName
+procName = label "process name" $ lexeme $ do
+ c <- lowerChar
+ cs <- takeWhileP Nothing (\x -> isAlphaNum x || x == '_' || x == '-')
+ return $ ProcName $ TL.toStrict (c `TL.cons` cs)
+
+identifier :: TestParser Text
+identifier = do
+ lexeme $ TL.toStrict <$> takeWhile1P Nothing (\x -> isAlphaNum x || x == '_')
+
+varName :: TestParser VarName
+varName = VarName <$> identifier
+
+newVarName :: forall a. ExprType a => TestParser (TypedVarName a)
+newVarName = do
+ off <- stateOffset <$> getParserState
+ name <- TypedVarName <$> varName
+ addVarName off name
+ return name
+
+addVarName :: forall a. ExprType a => Int -> TypedVarName a -> TestParser ()
+addVarName off (TypedVarName name) = do
+ gets (lookup name . testVars) >>= \case
+ Just _ -> parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $
+ T.pack "variable '" <> textVarName name <> T.pack "' already exists"
+ Nothing -> return ()
+ modify $ \s -> s { testVars = (name, SomeExprType @a Proxy) : testVars s }
+
+someExpansion :: TestParser SomeExpr
+someExpansion = do
+ void $ char '$'
+ choice
+ [do name <- VarName . TL.toStrict <$> takeWhile1P Nothing (\x -> isAlphaNum x || x == '_')
+ SomeVarValue (_ :: a) <- lookupVar name
+ return $ SomeExpr $ Variable @a name
+ , between (char '{') (char '}') someExpr
+ ]
+
+stringExpansion :: ExprType a => Text -> (forall b. ExprType b => Expr b -> [Maybe (Expr a)]) -> TestParser (Expr a)
+stringExpansion tname conv = do
+ off <- stateOffset <$> getParserState
+ SomeExpr e <- someExpansion
+ let err = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $ T.concat
+ [ tname, T.pack " expansion not defined for '", textExprType e, T.pack "'" ]
+
+ maybe err return $ listToMaybe $ catMaybes $ conv e
+
+numberLiteral :: TestParser SomeExpr
+numberLiteral = label "number" $ lexeme $ do
+ x <- L.scientific
+ choice
+ [ return (SomeExpr $ Pure (x / 100)) <* void (char ('%'))
+ , if base10Exponent x == 0
+ then return $ SomeExpr $ Pure (coefficient x)
+ else return $ SomeExpr $ Pure x
+ ]
+
+quotedString :: TestParser (Expr Text)
+quotedString = label "string" $ lexeme $ do
+ void $ char '"'
+ let inner = choice
+ [ char '"' >> return []
+ , takeWhile1P Nothing (`notElem` ['\"', '\\', '$']) >>= \s -> (Pure (TL.toStrict s):) <$> inner
+ ,do void $ char '\\'
+ c <- choice
+ [ char '\\' >> return '\\'
+ , char '"' >> return '"'
+ , char '$' >> return '$'
+ , char 'n' >> return '\n'
+ , char 'r' >> return '\r'
+ , char 't' >> return '\t'
+ ]
+ (Pure (T.singleton c) :) <$> inner
+ ,do e <- stringExpansion (T.pack "string") $ \e ->
+ [ cast e
+ , fmap (T.pack . show @Integer) <$> cast e
+ , fmap (T.pack . show @Scientific) <$> cast e
+ ]
+ (e:) <$> inner
+ ]
+ Concat <$> inner
+
+regex :: TestParser (Expr Regex)
+regex = label "regular expression" $ lexeme $ do
+ void $ char '/'
+ let inner = choice
+ [ char '/' >> return []
+ , takeWhile1P Nothing (`notElem` ['/', '\\', '$']) >>= \s -> (Pure (RegexPart (TL.toStrict s)) :) <$> inner
+ ,do void $ char '\\'
+ s <- choice
+ [ char '/' >> return (Pure $ RegexPart $ T.singleton '/')
+ , anySingle >>= \c -> return (Pure $ RegexPart $ T.pack ['\\', c])
+ ]
+ (s:) <$> inner
+ ,do e <- stringExpansion (T.pack "regex") $ \e ->
+ [ cast e
+ , fmap RegexString <$> cast e
+ , fmap (RegexString . T.pack . show @Integer) <$> cast e
+ , fmap (RegexString . T.pack . show @Scientific) <$> cast e
+ ]
+ (e:) <$> inner
+ ]
+ expr <- Regex <$> inner
+ _ <- eval expr -- test regex parsing with empty variables
+ return expr
+
+list :: TestParser SomeExpr
+list = label "list" $ do
+ symbol "["
+ SomeExpr x <- someExpr
+
+ let enumErr off = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $
+ "list range enumeration not defined for '" <> textExprType x <> "'"
+ choice
+ [do symbol "]"
+ return $ SomeExpr $ fmap (:[]) x
+
+ ,do off <- stateOffset <$> getParserState
+ osymbol ".."
+ ExprEnumerator fromTo _ <- maybe (enumErr off) return $ exprEnumerator x
+ y <- typedExpr
+ symbol "]"
+ return $ SomeExpr $ fromTo <$> x <*> y
+
+ ,do symbol ","
+ y <- typedExpr
+
+ choice
+ [do off <- stateOffset <$> getParserState
+ osymbol ".."
+ ExprEnumerator _ fromThenTo <- maybe (enumErr off) return $ exprEnumerator x
+ z <- typedExpr
+ symbol "]"
+ return $ SomeExpr $ fromThenTo <$> x <*> y <*> z
+
+ ,do symbol ","
+ xs <- listOf typedExpr
+ symbol "]"
+ return $ SomeExpr $ foldr (liftA2 (:)) (Pure []) (x:y:xs)
+ ]
+ ]
+
+data SomeUnOp = forall a b. (ExprType a, ExprType b) => SomeUnOp (a -> b)
+
+applyUnOp :: forall a b sa.
+ (ExprType a, ExprType b, ExprType sa) =>
+ (a -> b) -> Expr sa -> Maybe (Expr b)
+applyUnOp op x = do
+ Refl :: a :~: sa <- eqT
+ return $ op <$> x
+
+data SomeBinOp = forall a b c. (ExprType a, ExprType b, ExprType c) => SomeBinOp (a -> b -> c)
+
+applyBinOp :: forall a b c sa sb.
+ (ExprType a, ExprType b, ExprType c, ExprType sa, ExprType sb) =>
+ (a -> b -> c) -> Expr sa -> Expr sb -> Maybe (Expr c)
+applyBinOp op x y = do
+ Refl :: a :~: sa <- eqT
+ Refl :: b :~: sb <- eqT
+ return $ op <$> x <*> y
+
+someExpr :: TestParser SomeExpr
+someExpr = join inner <?> "expression"
+ where
+ inner = makeExprParser term table
+
+ parens = between (symbol "(") (symbol ")")
+
+ term = parens inner <|> literal <|> variable <?> "term"
+
+ table = [ [ recordSelector
+ ]
+ , [ prefix "-" $ [ SomeUnOp (negate @Integer)
+ , SomeUnOp (negate @Scientific)
+ ]
+ ]
+ , [ binary "*" $ [ SomeBinOp ((*) @Integer)
+ , SomeBinOp ((*) @Scientific)
+ ]
+ {- TODO: parsing issues with regular expressions
+ , binary "/" $ [ SomeBinOp (div @Integer)
+ , SomeBinOp ((/) @Scientific)
+ ]
+ -}
+ ]
+ , [ binary "+" $ [ SomeBinOp ((+) @Integer)
+ , SomeBinOp ((+) @Scientific)
+ ]
+ , binary "-" $ [ SomeBinOp ((-) @Integer)
+ , SomeBinOp ((-) @Scientific)
+ ]
+ ]
+ , [ binary' "==" (\op xs ys -> length xs == length ys && and (zipWith op xs ys)) $
+ [ SomeBinOp ((==) @Integer)
+ , SomeBinOp ((==) @Scientific)
+ , SomeBinOp ((==) @Text)
+ ]
+ , binary' "/=" (\op xs ys -> length xs /= length ys || or (zipWith op xs ys)) $
+ [ SomeBinOp ((/=) @Integer)
+ , SomeBinOp ((/=) @Scientific)
+ , SomeBinOp ((/=) @Text)
+ ]
+ ]
+ ]
+
+ prefix :: String -> [SomeUnOp] -> Operator TestParser (TestParser SomeExpr)
+ prefix name ops = Prefix $ do
+ off <- stateOffset <$> getParserState
+ void $ osymbol name
+ return $ \p -> do
+ SomeExpr e <- p
+ let err = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $ T.concat
+ [T.pack "operator '", T.pack name, T.pack "' not defined for '", textExprType e, T.pack "'"]
+ maybe err return $ listToMaybe $ catMaybes $ map (\(SomeUnOp op) -> SomeExpr <$> applyUnOp op e) ops
+
+ binary :: String -> [SomeBinOp] -> Operator TestParser (TestParser SomeExpr)
+ binary name = binary' name (undefined :: forall a b. (a -> b -> Void) -> [a] -> [b] -> Integer)
+ -- use 'Void' that can never match actually used type to disable recursion
+
+ binary' :: forall c c'. (Typeable c, ExprType c')
+ => String
+ -> (forall a b. (a -> b -> c) -> [a] -> [b] -> c')
+ -> [SomeBinOp]
+ -> Operator TestParser (TestParser SomeExpr)
+ binary' name listmap ops = InfixL $ do
+ off <- stateOffset <$> getParserState
+ void $ osymbol name
+
+ return $ \p q -> do
+ SomeExpr e <- p
+ SomeExpr f <- q
+
+ let eqT' :: forall r s t. (Typeable r, Typeable s, Typeable t) => (r -> s -> t) -> Maybe ((r -> s -> t) :~: (r -> s -> c))
+ eqT' _ = eqT
+
+ let proxyOf :: proxy a -> Proxy a
+ proxyOf _ = Proxy
+
+ let tryop :: forall a b d sa sb.
+ (ExprType a, ExprType b, ExprType d, ExprType sa, ExprType sb) =>
+ (a -> b -> d) -> Proxy sa -> Proxy sb -> Maybe SomeExpr
+ tryop op pe pf = msum
+ [ SomeExpr <$> applyBinOp op e f
+ , do Refl <- eqT' op
+ ExprListUnpacker _ une <- exprListUnpacker pe
+ ExprListUnpacker _ unf <- exprListUnpacker pf
+ tryop (listmap op) (une pe) (unf pf)
+ ]
+
+ let err = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $ T.concat
+ [T.pack "operator '", T.pack name, T.pack "' not defined for '", textExprType e, T.pack "' and '", textExprType f, T.pack "'"]
+ maybe err return $ listToMaybe $ catMaybes $ map (\(SomeBinOp op) -> tryop op (proxyOf e) (proxyOf f)) ops
+
+ recordSelector :: Operator TestParser (TestParser SomeExpr)
+ recordSelector = Postfix $ fmap (foldl1 (flip (.))) $ some $ do
+ void $ osymbol "."
+ off <- stateOffset <$> getParserState
+ m <- identifier
+ return $ \p -> do
+ SomeExpr e <- p
+ let err = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $ T.concat
+ [ T.pack "value of type ", textExprType e, T.pack " does not have member '", m, T.pack "'" ]
+ maybe err return $ applyRecordSelector e <$> lookup m recordMembers
+
+ applyRecordSelector :: ExprType a => Expr a -> RecordSelector a -> SomeExpr
+ applyRecordSelector e (RecordSelector f) = SomeExpr $ f <$> e
+
+ literal = label "literal" $ choice
+ [ return <$> numberLiteral
+ , return . SomeExpr <$> quotedString
+ , return . SomeExpr <$> regex
+ , return <$> list
+ ]
+
+ variable = label "variable" $ do
+ name <- varName
+ SomeVarValue (_ :: a) <- lookupVar name
+ return $ return $ SomeExpr $ Variable @a name
+
+typedExpr :: forall a. ExprType a => TestParser (Expr a)
+typedExpr = do
+ off <- stateOffset <$> getParserState
+ SomeExpr e <- someExpr
+ let err = parseError $ FancyError off $ S.singleton $ ErrorFail $ T.unpack $ T.concat
+ [ T.pack "expected '", textExprType @a Proxy, T.pack "', expression has type '", textExprType e, T.pack "'" ]
+ maybe err return $ cast e
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 02:34:20 +0000