diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Parser.hs | 27 | ||||
| -rw-r--r-- | src/Reducer.hs | 12 |
2 files changed, 20 insertions, 19 deletions
diff --git a/src/Parser.hs b/src/Parser.hs index 44bae87..82fe98b 100644 --- a/src/Parser.hs +++ b/src/Parser.hs @@ -18,15 +18,15 @@ sc :: Parser () sc = void $ char ' ' infixOperator :: Parser String -infixOperator = some $ oneOf "!?*@:+-#$%^&<>/|~=" +infixOperator = some $ oneOf "!?*@.:+-#$%^&<>/|~=" prefixOperator :: Parser String -prefixOperator = some $ oneOf "!?*@:+-#$%^&<>/|~=" +prefixOperator = some $ oneOf "!?*@.:+-#$%^&<>/|~=" -- def identifier disallows the import prefix dots defIdentifier :: Parser String defIdentifier = - ((:) <$> (letterChar <|> char '_') <*> many (alphaNumChar <|> oneOf "?!'_-")) + ((:) <$> (letterChar <|> char '_') <*> many (alphaNumChar <|> oneOf "?!'_-*")) <|> ((\l i r -> [l] ++ i ++ [r]) <$> char '(' <*> infixOperator <*> char ')' ) <|> ((\p i -> p ++ [i]) <$> prefixOperator <*> char '(') @@ -35,7 +35,8 @@ defIdentifier = -- TODO: write as extension to defIdentifier identifier :: Parser String identifier = - ((:) <$> (letterChar <|> char '_') <*> many (alphaNumChar <|> oneOf "?!'_-.")) + ((:) <$> (letterChar <|> char '_') <*> many (alphaNumChar <|> oneOf "?!'_-*.") + ) <?> "identifier" namespace :: Parser String @@ -84,16 +85,20 @@ specialEscape = parseString :: Parser Expression parseString = do - str <- between - (char '\"') - (char '\"') - (some $ (char '\\' *> specialEscape) <|> (satisfy (`notElem` "\"\\"))) - pure (stringToExpression str) <?> "string" + str <- + between + (char '\"') + (char '\"') + (some $ (char '\\' *> specialEscape) <|> (satisfy (`notElem` "\"\\"))) + <?> "quoted string" + pure $ stringToExpression str parseChar :: Parser Expression parseChar = do - ch <- between (char '\'') (char '\'') (satisfy (`notElem` "\"\\")) - pure (charToExpression ch) <?> "char" + ch <- + between (char '\'') (char '\'') (satisfy (`notElem` "\"\\")) + <?> "quoted char" + pure $ charToExpression ch parseVariable :: Parser Expression parseVariable = do diff --git a/src/Reducer.hs b/src/Reducer.hs index 87d8859..ddf2439 100644 --- a/src/Reducer.hs +++ b/src/Reducer.hs @@ -34,14 +34,10 @@ step (Application e1 e2) = Application (step e1) (step e2) step (Abstraction e) = Abstraction (step e) step _ = error "invalid" -reduceable :: Expression -> Bool -reduceable (Bruijn _) = False -reduceable (Variable _) = True -reduceable (Application (Abstraction _) _) = True -reduceable (Application e1 e2) = reduceable e1 || reduceable e2 -reduceable (Abstraction e) = reduceable e -reduceable _ = error "invalid" +-- until eq +converge :: Eq a => (a -> a) -> a -> a +converge = until =<< ((==) =<<) -- alpha conversion is not needed with de bruijn indexing reduce :: Expression -> Expression -reduce = until (not . reduceable) step +reduce = converge step |