diff options
| -rw-r--r-- | src/Language/SimpleShell/Parser/Expr.hs | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/src/Language/SimpleShell/Parser/Expr.hs b/src/Language/SimpleShell/Parser/Expr.hs index d0bd01a..57b1d22 100644 --- a/src/Language/SimpleShell/Parser/Expr.hs +++ b/src/Language/SimpleShell/Parser/Expr.hs @@ -28,22 +28,26 @@ import qualified Text.Megaparsec.Char.Lexer as L (charLiteral, decimal) exprP :: Parser TypedExpr exprP - = makeExprParser termP binaryOperatorTable + = makeExprParser weakTermP binaryOperatorTable + +weakTermP :: Parser TypedExpr +weakTermP + = strongTermP + <|> unaryOpP <|> builtinUnaryFunP <|> funP -termP :: Parser TypedExpr -termP +strongTermP :: Parser TypedExpr +strongTermP = literalP <|> varP - <|> unaryOpP <|> lexeme (char '(') *> exprP <* lexeme (char ')') --- | Parse expression with fixed type. -exprP' :: String -> SimpleType -> Parser Expr -exprP' errMsg t = do - (t', e) <- exprP +-- | Parse "strong" term with fixed type. +strongTermP' :: String -> SimpleType -> Parser Expr +strongTermP' errMsg t = do + (t', e) <- strongTermP if t == t' then return e else fail errMsg @@ -71,7 +75,7 @@ funP :: Parser TypedExpr funP = do fname <- lexeme funNameP (t', ts) <- lookupFun fname - args <- mapM (exprP' "Type mismatch with function signature.") ts + args <- mapM (strongTermP' "Type mismatch with function signature.") ts return (t', FunCall fname args) @@ -169,8 +173,8 @@ unaryOperators, builtinUnaryFuns :: [UnaryParser] unaryOpP, builtinUnaryFunP :: Parser TypedExpr (unaryOpP, builtinUnaryFunP) = - ( asum $ map (aux "unary operator" termP) unaryOperators - , asum $ map (aux "builtin unary function" exprP) builtinUnaryFuns + ( asum $ map (aux "unary operator" weakTermP ) unaryOperators + , asum $ map (aux "builtin unary function" strongTermP) builtinUnaryFuns ) where aux :: String -> Parser TypedExpr -> UnaryParser -> Parser TypedExpr |