diff options
Diffstat (limited to 'src/Parser.hs')
| -rw-r--r-- | src/Parser.hs | 32 |
1 files changed, 15 insertions, 17 deletions
diff --git a/src/Parser.hs b/src/Parser.hs index b6ab9fb..1669bcd 100644 --- a/src/Parser.hs +++ b/src/Parser.hs @@ -1,19 +1,11 @@ module Parser where import Data.Functor.Identity +import Helper import Text.Parsec import Text.Parsec.Language import qualified Text.Parsec.Token as Token -data Error = SyntaxError ParseError | UndeclaredFunction String | DuplicateFunction String | InvalidIndex Int | FatalError String -instance Show Error where - show (SyntaxError err) = show err - show (UndeclaredFunction err) = "ERROR: undeclared function " <> show err - show (DuplicateFunction err) = "ERROR: duplicate function " <> show err - show (InvalidIndex err) = "ERROR: invalid index " <> show err - show (FatalError err) = show err -type Failable = Either Error - languageDef :: GenLanguageDef String u Identity languageDef = emptyDef { Token.commentLine = "#" , Token.identStart = letter @@ -35,15 +27,14 @@ reservedOp = Token.reservedOp lexer parens :: Parser a -> Parser a parens = Token.parens lexer -data Expression = Bruijn Int | Variable String | Abstraction Expression | Application Expression Expression - deriving (Ord, Eq, Show) -data Instruction = Define String Expression | Evaluate Expression | Comment String - deriving (Show) +almostAnything :: Parser String +almostAnything = + many1 $ oneOf ".`#~@$%^&*_+-=|;',/?[]<>(){} " <|> letter <|> digit parseAbstraction :: Parser Expression parseAbstraction = do reservedOp "[" - exp <- parseExpression <|> parseBruijn + exp <- parseExpression reservedOp "]" pure $ Abstraction exp @@ -65,11 +56,14 @@ parseVariable = do pure $ Variable var parseSingleton :: Parser Expression -parseSingleton = parseAbstraction <|> parens parseApplication <|> parseVariable +parseSingleton = + parseBruijn <|> parseAbstraction <|> parens parseApplication <|> parseVariable parseExpression :: Parser Expression parseExpression = do + spaces expr <- parseApplication <|> parseSingleton + spaces pure expr parseEvaluate :: Parser Instruction @@ -90,10 +84,14 @@ parseReplDefine = do Define var <$> parseExpression parseComment :: Parser Instruction -parseComment = string "#" >> Comment <$> many letter +parseComment = string "#" >> Comment <$> almostAnything + +parseLoad :: Parser Instruction +parseLoad = string ":load " >> Load <$> almostAnything parseLine :: Parser Instruction parseLine = try parseDefine <|> parseComment parseReplLine :: Parser Instruction -parseReplLine = try parseReplDefine <|> parseComment <|> parseEvaluate +parseReplLine = + try parseReplDefine <|> parseComment <|> parseEvaluate <|> parseLoad |