diff options
Diffstat (limited to 'lore/Language/Bs/Expr.hs')
-rw-r--r-- | lore/Language/Bs/Expr.hs | 154 |
1 files changed, 0 insertions, 154 deletions
diff --git a/lore/Language/Bs/Expr.hs b/lore/Language/Bs/Expr.hs deleted file mode 100644 index a39c7b6..0000000 --- a/lore/Language/Bs/Expr.hs +++ /dev/null @@ -1,154 +0,0 @@ -{-# LANGUAGE OverloadedStrings #-} -{-# LANGUAGE NoImplicitPrelude #-} -{-# LANGUAGE DeriveDataTypeable #-} -{-# LANGUAGE GeneralizedNewtypeDeriving #-} -module Language.Bs.Expr where - -import Data.String (String) -import Data.Text (Text) -import qualified Data.Text as T -import GHC.Show -import Protolude hiding (show) -import qualified Text.PrettyPrint.Leijen.Text as PP -import Text.PrettyPrint.Leijen.Text hiding ((<$>)) - -type Ctx = Map Text Expr -data Env = Env { env :: Ctx, fenv :: Ctx } - deriving (Eq) - -newtype Eval a = Eval { unEval :: ReaderT Env IO a } - deriving (Monad, Functor, Applicative, MonadReader Env, MonadIO) - -data IFunc = IFunc { fn :: [Expr] -> Eval Expr } - deriving (Typeable) - -instance Eq IFunc where - (==) _ _ = False - -data Expr - = Atom Text - | List [Expr] - | Numb Integer - | Tape Text - | IFun IFunc -- TODO: call this Kern - | Func IFunc Env - | Bool Bool - | Nil - deriving (Typeable, Eq) - -instance Show Expr where - show = T.unpack . ppexpr - -data LispErrorType - = NumArgs Integer [Expr] - | LengthOfList Text Int - | ExpectedList Text - | ParseError String - | TypeMismatch Text Expr - | BadSpecialForm Text - | NotFunction Expr - | UnboundVar Text - | Default Expr - | ReadFileError Text - deriving (Typeable) - -data LispError = LispError Expr LispErrorType - -instance Show LispErrorType where - show = T.unpack . ppexpr - -instance Show LispError where - show = T.unpack . ppexpr - -instance Exception LispErrorType -instance Exception LispError - -ppexpr :: Pretty a => a -> Text -ppexpr x = PP.displayTStrict (PP.renderPretty 1.0 70 (pretty x)) - ---prettyList :: [Doc] -> Doc ---prettyList = encloseSep lparen rparen PP.space - -instance Pretty Expr where - pretty v = - case v of - Atom a -> - textStrict a - - List ls -> - prettyList $ fmap pretty ls - - Numb n -> - integer n - - Tape t -> - textStrict "\"" <> textStrict t <> textStrict "\"" - - IFun _ -> - textStrict "<internal function>" - - Func _ _ -> - textStrict "<lambda function>" - - Bool True -> - textStrict "#t" - - Bool False -> - textStrict "#f" - - Nil -> - textStrict "'()" - -instance Pretty LispErrorType where - pretty err = case err of - NumArgs i args -> - textStrict "number of arguments" - <$$> textStrict "expected" - <+> textStrict (T.pack $ show i) - <$$> textStrict "received" - <+> textStrict (T.pack $ show $ length args) - - - LengthOfList txt i -> - textStrict "length of list in:" - <+> textStrict txt - <$$> textStrict "length:" - <+> textStrict (T.pack $ show i) - - ParseError txt -> - textStrict "cannot parse expr:" - <+> textStrict (T.pack txt) - - TypeMismatch txt expr -> - textStrict "type mismatch:" - <$$> textStrict txt - <$$> pretty expr - - BadSpecialForm txt -> - textStrict "bad special form:" - <$$> textStrict txt - - NotFunction expr -> - textStrict "not a function" - <$$> pretty expr - - UnboundVar txt -> - textStrict "unbound variable:" - <$$> textStrict txt - - Default _ -> - textStrict "default error" - - ReadFileError txt -> - textStrict "error reading file:" - <$$> textStrict txt - - ExpectedList txt -> - textStrict "expected list:" - <$$> textStrict txt - -instance Pretty LispError where - pretty (LispError expr typ) = - textStrict "error evaluating:" - <$$> indent 4 (pretty expr) - <$$> pretty typ |