diff --git a/LICENSE b/LICENSE new file mode 100644 --- /dev/null +++ b/LICENSE @@ -0,0 +1,675 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. We, the Free Software Foundation, use the +GNU General Public License for most of our software; it applies also to +any other work released this way by its authors. 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If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + Copyright (C) + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. + diff --git a/Octopus.hs b/Octopus.hs new file mode 100644 --- /dev/null +++ b/Octopus.hs @@ -0,0 +1,175 @@ +module Octopus where + +import Import +import qualified Data.Sequence as Seq +import qualified Data.Map as Map + +import Control.Monad.State +import Control.Monad.Reader +import System.IO.Error +import Control.Concurrent.MVar + +import Octopus.Data +import Octopus.Parser (parseOctopusFile) +import qualified Octopus.Primitive as Oct +import Octopus.Basis +import Octopus.Shortcut +import Octopus.Libraries + + +eval :: ImportsCache -> Val -> Val -> IO Val +eval cache env code = evalStateT (runReaderT (reduce code) cache) startState + where + startState = MState { environ = env --Ob Map.empty + , control = [NormK []] + } + + +reduce :: Val -> Machine Val +reduce x@(Nm _) = done x +reduce x@(By _) = done x +reduce x@(Tx _) = done x +reduce x@(Fp _) = done x +reduce x@(Tg _) = done x +reduce x@(Ab _ _) = done x +reduce x@(Cl _ _ _) = done x +reduce x@(Ce _) = done x +reduce x@(Ar _) = done x +reduce x@(Pr _) = done x +reduce sq@(Sq xs) = case toList xs of + [] -> done sq + (x:xs) -> push (Es [] xs) >> reduce x +reduce ob@(Ob m) = case ensureCombination ob of + Just (f, x) -> push (Op x) >> reduce f + Nothing -> case Map.toList m of + [] -> done (mkOb []) + ((k,v):xs) -> push (Eo k [] xs) >> reduce v +reduce (Sy x) = gets environ >>= \env -> case Oct.resolveSymbol x env of + Just val -> done val + Nothing -> do + env <- gets environ + error $ "TODO unbound symbol: " ++ show x ++ "\n" ++ show env + +combine :: Val -> Val -> Machine Val +combine (Pr Vau) x = case x of + Sq xs -> case toList xs of + [var, ast] -> do + env <- gets environ + done $ Cl var ast env + _ -> error "raise wrong number of args to primitive vau" + _ -> error "raise invalid args to primitive vau" +combine f@(Pr _) x = push (Ap f) >> reduce x +combine f x = case ensureClosure f of --all of these are operatives + Just (var, ast, env) -> do + caller <- gets environ + let x' = mkSq [caller, x] + case Oct.match var x' of + Right env' -> swapEnv (env' `Oct.extend` env) >> reduce ast + Left err -> error "raise match failure" + _ -> error $ "raise not a combiner:\n" ++ show f + +apply :: Val -> Val -> Machine Val +apply (Pr Eval) x = case ensureThunk x of + Just (env, ast) -> swapEnv env >> reduce ast + _ -> error $ "raise invalid args to primitive eval: " ++ show x +apply (Pr Ifz) x = case x of + Sq xs -> case toList xs of + [p, c, a] -> done $ Oct.ifz p c a + _ -> error "raise wrong number of args to primitive Ifz" + _ -> error "raise invalid args to primitive Ifz" +apply (Pr Imp) x = impFile x +apply (Pr Extends) x = case x of + Sq xs -> case toList xs of + [] -> done $ mkOb [] + xs -> done $ foldr1 Oct.extend xs + _ -> error "raise invalid args to primitive Extends" +apply (Pr pr) x = + case lookup pr table of + Just f -> case f pr x of + Right val -> done val + Left err -> error $ "raise some error in primitive " ++ show pr + Nothing -> error $ "unknown primitive " ++ show pr + where + table = + [ (Match, binary Oct.match) + + , (Delete, binary Oct.delete) + , (Keys, unary Oct.keys) + , (Get, binary Oct.get) + + , (Eq, binary Oct.eq) + , (Neq, binary Oct.neq) + , (Lt, binary Oct.lt) + , (Lte, binary Oct.lte) + , (Gt, binary Oct.gt) + , (Gt, binary Oct.gt) + + , (Add, binary Oct.add) + , (Sub, binary Oct.sub) + , (Mul, binary Oct.mul) + , (Div, binary Oct.div) + + , (Len, unary Oct.len) + , (Cat, binary Oct.cat) + , (Cut, binary Oct.cut) + + , (Numer, unary Oct.numer) + , (Denom, unary Oct.denom) + , (NumParts, unary Oct.numParts) + ] + binary :: (Val -> Val -> Fallible Val) -> Primitive -> Val -> Fallible Val + binary op pr x = case x of + Sq xs -> case toList xs of + [a, b] -> op a b + _ -> error $ "raise wrong number of args to primitive " ++ show pr + _ -> error $ "raise invalid args to primitive " ++ show pr + unary :: (Val -> Fallible Val) -> Primitive -> Val -> Fallible Val + unary op pr x = op x +apply f x = error "TODO apply" + +done :: Val -> Machine Val +done x = do + k <- gets control + case k of + [] -> return x + (NormK []):_ -> pop >> done x + (NormK (Re _:_)):_ -> pop >> done x + (NormK (Es xs []:_)):_ -> pop >> done (Sq . Seq.fromList $ reverse (x:xs)) + (NormK (Es xs (x':xs'):_)):_ -> replace (Es (x:xs) xs') >> reduce x' + (NormK (Eo k xs []:_)):_ -> pop >> done (Ob . Map.fromList $ (k,x):xs) + (NormK (Eo k xs ((k',x'):xs'):_)):_ -> replace (Eo k' ((k,x):xs) xs') >> reduce x' + (NormK (Op arg:ks)):kss -> pop >> combine x arg + (NormK (Ap f:ks)):kss -> pop >> apply f x + (ImptK _ slot):ks -> liftIO (slot `putMVar` Right x) >> pop >> done x + + +impFile :: Val -> Machine Val +impFile (Tx pathstr) = do + let path = pathstr --FIXME normalize path + path' = unpack path + --TODO check against builtin files, or else pre-populate the cache + --TODO check the path against the current imports on stack to avoid circular import + cache_var <- ask + cache <- liftIO $ takeMVar cache_var + case Map.lookup path cache of + Just loaded_var -> do + liftIO $ cache_var `putMVar` cache + val_e <- liftIO $ readMVar loaded_var + case val_e of + Right val -> done val + Left err -> error $ "raise exception " ++ show err + Nothing -> do + loading_var <- liftIO newEmptyMVar + liftIO $ cache_var `putMVar` Map.insert path loading_var cache + contents_e <- liftIO $ tryIOError $ readFile path' + case contents_e of + Right contents -> do + swapEnv startData + pushK (ImptK path loading_var) + case parseOctopusFile path' contents of + Right val -> reduce val --TODO consider which env to start a file off with + Left err -> error "raise SyntaxError" --FIXME also don't forget to fill the loading_var + Left err -> error "raise ImportError" --FIXME also don't forget to fill the loading_var +impFile _ = error "TODO raise TypeError" + + diff --git a/Octopus/Basis.hs b/Octopus/Basis.hs new file mode 100644 --- /dev/null +++ b/Octopus/Basis.hs @@ -0,0 +1,98 @@ +{-| This module contains values that help create and manipulate Octopus + values that are used by the interpreter, but not strictly primitive, + that is, they could just as easily be defined in user-space, as long + as the machine could get at them. +-} +module Octopus.Basis ( + mkVau + -- * Basic Protocols + -- ** Combination + , mkCall + , callOpr + , callArg + , ensureCombination + -- ** Closure + , mkClosure + , ensureClosure + -- ** Suspension + , mkThunk + , ensureThunk + + , module Octopus.Shortcut + ) where + +import Import +import qualified Data.Sequence as Seq +import qualified Data.Map as Map + +import Octopus.Data +import Octopus.Shortcut + + +mkVau :: String -> String -> Val -> Val +mkVau e arg body = mkCall (Pr Vau) (mkSq [mkSq [Sy $ intern e, Sy $ intern arg], body]) + + +{-| Construct a combination: an object with a + @__car__@ slot and a @__cdr__@ slot. +-} +mkCall :: Val -- ^ Combiner (@__car__@) + -> Val -- ^ Argument (@__cdr__@) + -> Val +mkCall f x = mkOb [(callOpr, f), (callArg, x)] + +{-| Extract a (combiner, argument) pair from a + combination-responsive object. +-} +ensureCombination :: Val -> Maybe (Val, Val) +ensureCombination (Ob ob) = (,) <$> Map.lookup callOpr ob + <*> Map.lookup callArg ob +ensureCombination _ = Nothing + +{-| Combiner slot name in a combination (aka. application) -} +callOpr :: Symbol +callOpr = intern "__car__" +{-| Argument slot name in a combination (aka. application) -} +callArg :: Symbol +callArg = intern "__cdr__" + + +{-| Construct a closure: an object with @__var__@, + @__ast__@ and @__env__@ slots. +-} +mkClosure :: Val -- ^ Body (@__ast__@) + -> Val -- ^ Static environment (@__env__@) + -> Val -- ^ Parameter (@__arg__@) + -> Val +mkClosure var ast env = Cl var ast env + +{-| Extract a (body, environment, parameter) triple from + a closure-responsive object. +-} +ensureClosure :: Val -> Maybe (Val, Val, Val) +ensureClosure (Cl var ast env) = Just (var, ast, env) +ensureClosure _ = Nothing + + +{-| Construct a thunk: a (environment, body) pair. -} +mkThunk :: Val -- ^ Environment (second element) + -> Val -- ^ Body (first element) + -> Val +mkThunk env ast = Sq $ Seq.fromList [env, ast] + +{-| Extract a (environment, body) pair from a thunk-responsive pair. -} +ensureThunk :: Val -> Maybe (Val, Val) +ensureThunk (Sq xs) = case toList xs of + [env, ast] -> Just (env, ast) + _ -> Nothing +ensureThunk _ = Nothing + + + + + + + + + + diff --git a/Octopus/Data.hs b/Octopus/Data.hs new file mode 100644 --- /dev/null +++ b/Octopus/Data.hs @@ -0,0 +1,132 @@ +module Octopus.Data where + +import Import +import qualified Data.Sequence as Seq +import qualified Data.Map as Map +import Control.Monad.Reader +import Control.Monad.State +import Control.Concurrent.MVar (MVar) + + +type Fallible = Either Val + + +data Val = Nm Rational -- ^ Rational number + | By ByteString -- ^ Bytes + | Tx Text -- ^ Text data + | Fp Handle -- ^ Input/output handle + | Sy Symbol -- ^ Symbol, aka. identifier + | Tg Word -- ^ Unique tag + | Ab Word Val -- ^ Abstract data + | Sq (Seq Val) -- ^ Sequence, aka. list + | Ob (Map Symbol Val) -- ^ Symbol-value map, aka. object + | Cl Val Val Val -- ^ Operative closure + | Ce (IORef Val) -- ^ Reference cell + | Ar (IOArray Int Val) -- ^ Mutable array + | Pr Primitive -- ^ Primitive operations + | Pt Int -- ^ Control prompt --TODO consider removing this in favor of using tags and a handler protocol + | Ks [Control] -- ^ Control stack + --TODO bytestring/buffer/bytes/other name? + --TODO concurrency + deriving (Eq) +data Primitive = Vau | Eval | Match | Ifz | Imp + | Eq | Neq | Lt | Lte | Gt | Gte + | Add | Mul | Sub | Div + | Numer | Denom | NumParts + --TODO By data primitives + --TODO Tx data primitives + --TODO Fp data primitives + --TODO Sy data primitives + --TODO Tg data primitives + | Wrap Word | Unwrap Word + | Len | Cat | Cut + | Extends | Delete | Keys | Get + --TODO Ce data primitives + --TODO Ar data primitives + --TODO Pt/Ks data primitives + deriving (Eq, Show) + + + +type FileCache = MVar (Either Val Val) +type ImportsCache = MVar (Map Text FileCache) +data MState = MState { environ :: Val, control :: [Control] } + +type Machine = ReaderT ImportsCache (StateT MState IO) + + +data Context = Op Val -- ^ Hole must be a combiner, val is the uneval'd argument + | Ap Val -- ^ Hole is the argument, apply held value to it + | Re Val -- ^ Restore an environment before continuing + | Es [Val] [Val] -- ^ Left-to-right sequence evaluation + | Eo Symbol [(Symbol, Val)] [(Symbol, Val)] -- ^ Object evaluation + deriving (Eq, Show) +data Control = NormK [Context] + | HndlK Val + --TODO onEnter/onSuccess/onFail + | ImptK Text (MVar (Fallible Val)) + deriving (Eq) +instance Show Control where + show (NormK k) = "NormK " ++ show k + show (HndlK x) = "HndlK " ++ show x + show (ImptK path slot) = "ImptK " ++ show path + + +push :: Context -> Machine () +push k = do + (NormK ks):kss <- gets control + modify $ \s -> s { control = (NormK (k:ks)):kss } + --FIXME remember that when I push a handler or a winding protect, I also need to push an environment restore +pushK :: Control -> Machine () +pushK k@(NormK _) = do + ks <- gets control + modify $ \s -> s { control = k:ks } +pushK k = do + ks <- gets control + modify $ \s -> s { control = (NormK []):k:ks } +pop :: Machine () +pop = do + stack <- gets control + case stack of + (NormK []):kss -> modify $ \s -> s { control = kss } + (NormK (Re env:ks)):kss -> modify $ \s -> s { environ = env, control = (NormK ks):kss } + (NormK (_:ks)):kss -> modify $ \s -> s { control = (NormK ks):kss } + (ImptK _ _):ks -> modify $ \s -> s { control = ks } +replace :: Context -> Machine () +replace k = do + stack <- gets control + case stack of + (NormK []):kss -> modify $ \s -> s { control = (NormK [k]):kss } + (NormK (_:ks)):kss -> modify $ \s -> s { control = (NormK (k:ks)):kss } + (ImptK _ _):ks -> pop >> replace k +swapEnv :: Val -> Machine () +swapEnv env' = do + env <- gets environ + (NormK ks):kss <- gets control + case ks of + (Re _):_ -> modify $ \s -> s { environ = env' } --allows tail recursion by not restoring environments that will immediately be thrown away by a second restoration + ks -> modify $ \s -> s { environ = env', control = (NormK ((Re env):ks)):kss } + + +instance Show Val where + show (Nm nm) | denominator nm == 1 = show $ numerator nm + | otherwise = show (numerator nm) ++ "/" ++ show (denominator nm) + show (By bytes) = "b" ++ show bytes --FIXME show with \x?? for non-ascii printable chars + show (Tx text) = show text --FIXME show using Octopus encoding, not Haskell + show (Fp _) = "" --TODO at least show some metadata + show (Sy sy) = show sy + show (Tg i) = "" + show (Ab tag x) = "" + show (Sq xs) = "[" ++ intercalate ", " (show <$> toList xs) ++ "]" + show (Ob m) = case getCombo m of + Nothing -> "{" ++ intercalate ", " (showPair <$> Map.toList m) ++ "}" + Just (f, x) -> "(" ++ show f ++ " " ++ show x ++ ")" + where + showPair (k,v) = show k ++ ": " ++ show v + getCombo ob = case (Map.lookup (intern "__car__") ob, Map.lookup (intern "__cdr__") ob) of + (Just f, Just x) -> if length (Map.keys ob) == 2 then Just (f, x) else Nothing + _ -> Nothing + show (Cl var ast env) = "" + show (Ce x) = "" --TODO show contents + show (Ar xs) = "" --TODO show contents + show (Pr f) = "<" ++ show f ++ ">" diff --git a/Octopus/Libraries.hs b/Octopus/Libraries.hs new file mode 100644 --- /dev/null +++ b/Octopus/Libraries.hs @@ -0,0 +1,94 @@ +module Octopus.Libraries where + +import Import +import Octopus.Data +import Octopus.Basis + + +startData = mkOb [ + --- Non-data --- + (intern "__vau__", Pr Vau) + , (intern "__match__", Pr Match) + , (intern "__eval__", Pr Eval) + , (intern "__ifz!__", Pr Ifz) + , (intern "__import__", Pr Imp) + --- Relationals --- + , (intern "__eq__", Pr Eq) + , (intern "__neq__", Pr Neq) + , (intern "__lt__", Pr Lt) + , (intern "__lte__", Pr Lte) + , (intern "__gt__", Pr Gt) + , (intern "__gte__", Pr Gt) + --- Arithmetic --- + , (intern "__add__", Pr Add) + , (intern "__mul__", Pr Mul) + , (intern "__sub__", Pr Sub) + , (intern "__div__", Pr Div) + --- Numbers --- + , (intern "__numer__", Pr Numer) + , (intern "__denom__", Pr Denom) + , (intern "__numparts__", Pr NumParts) + --- Lists --- + , (intern "__len__", Pr Len) + , (intern "__cat__", Pr Cat) + , (intern "__cut__", Pr Cut) + --- Xonses --- + , (intern "__extends__", Pr Extends) + , (intern "__del__", Pr Delete) + , (intern "__keys__", Pr Keys) + --TODO __lookup__ + --- Niceties --- + , (intern "vau", vauDef) + , (intern "__get__", getDef) + , (intern "__let__", letDef) + , (intern "__lambda__", lambdaDef) + , (intern "__quote__", quoteDef) + ] + +vauDef = Cl + (mkSq [mkOb [], mkSy "x"]) + (mkCall (Pr Vau) (mkSq [mkSq [mkSy "static", mkSy "body"], + mkCall (Pr Vau) (mkSq [mkSy "arg", + mkCall (Pr Eval) (mkSq [ + mkCall (Pr Extends) (mkSq [ + mkCall (Pr Match) (mkSq [mkSy "x", mkSy "arg"]), + mkSy "static"]), + mkSy "body"])])])) + (mkOb []) + + +delDef = Cl + (mkSy "ob") + (mkCall (Pr Vau) (mkSq [mkSq [mkOb [], mkSy "x"], + mkCall (Pr Delete) (mkSq [mkCall (Pr Eval) (mkSy "ob"), mkSy "x"])])) + (mkOb []) + +getDef = Cl + (mkSq [mkOb [], mkSy "x"]) + (mkCall (Pr Vau) (mkSq [mkSy "ob", + mkCall (Pr Eval) (mkSq [mkCall (Pr Eval) (mkSy "ob"), mkSy "x"])])) + (mkOb []) + + +letDef = Cl + (mkSq [mkOb [], mkSy "x"]) + (mkCall (Pr Vau) (mkSq [mkSy "val", + mkCall (Pr Vau) (mkSq [mkSq [mkSy "e", mkSy "body"], + mkCall (Pr Eval) (mkSq + [ mkCall (Pr Extends) (mkSq + [ mkCall (Pr Match) (mkSq [mkSy "x", mkCall (Pr Eval) (mkSy "val")]) + , mkSy "e"]) + , mkSy "body"])])])) + (mkOb []) + +lambdaDef = Cl + (mkSq [mkOb [], mkSy "var"]) + (mkCall (Pr Vau) (mkSq [mkSq [mkSy "static", mkSy "ast"], + mkCall (Pr Vau) (mkSq [mkSy "arg", + mkCall (Pr Eval) (mkSq + [ mkCall (Pr Extends) (mkSq + [ mkCall (Pr Match) (mkSq [mkSy "var", mkCall (Pr Eval) (mkSy "arg")]) + , mkSy "static"]) + , mkSy "ast"])])])) + (mkOb []) +quoteDef = Cl (mkSq [mkOb [], mkSy "ast"]) (mkSy "ast") (mkOb []) diff --git a/Octopus/Parser.hs b/Octopus/Parser.hs new file mode 100644 --- /dev/null +++ b/Octopus/Parser.hs @@ -0,0 +1,211 @@ +{-| Parse Octopus source code. The Octopus grammar is: + +@ +file ::= (\ | \)* +defn ::= _field_ \ +expr ::= \ | \ | \ + | \ | \ | \ + | '(' \ ')' + +atom ::= _symbol_ | _number_ | _string_ | _heredoc_ | _accessor_ +list ::= '[' (\+ (',' \+)*)? ']' +object ::= '{' (_field_ \+ (',' _field_ \+)*)? '}' +combination ::= '(' \ \+ ')' +block ::= 'do' (\ | \)+ ';' +quotation ::= '`' \ + +symbol ::= \/\\/ - reserved + reserved = {'do'} +field ::= \/\:\/ +accessor ::= \/:\\/ +number ::= \/[+-]?(0[xX]\|0[oO]\|0[bB]\|\)\/ + decnum ::= \/\\d+(\\.\\d+\?|\\\/\\d+)?\/ + hexnum ::= \/\\x+(\\.\\x+([hH][+-]?\\x+)?|\\\/\\x+)?\/ + octnum ::= \/[0-7]+(\\.[0-7]+\?|\\\/[0-7]+)?\/ + binnum ::= \/[01]+(\\.[01]+\?|\\\/[01]+)?\/ + exponent ::= \/[eE][+-]?\\d+|[hH][+-]?\\x+\/ +string ::= \/\"([^\\\\\"]|\\\\[abefntv\'\"\\\\&]|\\\\\|\\\\\\s*\\n\\s*\\\\)*\"\/ + numescape ::= \/[oO][0-7]{3}|[xX][0-9a-fA-F]{2}|u[0-9a-fA-F]{4}|U0[0-9a-fA-F]{5}|U10[0-9a-fA-F]{4}\/ +heredoc ::= \/\#\<\<\\s*(?\'END\'\\w+)\\s*\\n.*?\\g{END}\/ +name ::= \/\\|-(\|-)\|-\/ + nametail = \/[^\#\\\\\"`()[]{}:;.,]*\/ + namehead = \/[^\#\\\\\"`()[]{}:;.,0-9-]\/ + +linecomment ::= \/#(?!\>\>)\\.*?\\n\/ +blockcomment ::= \/\#\\{([^\#}]+|\|\#[^{]|\\}[^\#])*\\}\#\/ +@ +-} +module Octopus.Parser where + +import Import + +import qualified Data.ByteString.Lazy as BS +import qualified Data.Text as T +import Text.Parsec ( Parsec, SourceName, ParseError + , try, (), unexpected, parserZero + , char, anyChar, eof) +import qualified Text.Parsec as P +import Language.Parse + +import Octopus.Data +import Octopus.Shortcut +import Octopus.Basis + + +type Parser = Parsec String () + +parseOctopusExpr :: SourceName -> String -> Either ParseError Val +parseOctopusExpr sourceName input = P.runParser (padded expr <* padded eof) () sourceName input + +parseOctopusFile :: SourceName -> String -> Either ParseError Val +parseOctopusFile sourceName input = P.runParser octopusFile () sourceName input + where + octopusFile = do + es <- P.many $ padded statement + padded eof + return $ loop es + loop [] = mkCall getenv (mkOb []) + loop (Left s:rest) = mkCall (mkDefn s) (loop rest) + loop (Right e:rest) = mkCall (mkExpr e) (loop rest) + getenv = (mkCall (Pr Vau) (mkSq [mkSq [mkSy "e", mkOb []], mkSy "e"])) + + +define :: Parser (Val, Val) +define = do + var <- try (expr <* char ':' <* whitespace) + body <- expr + return (var, body) + +expr :: Parser Val +expr = composite P.<|> atom + where + atom = P.choice [symbol, numberLit, textLit, heredoc, accessor] "atom" + composite = P.choice [block, combine, sq, ob, quote] + +statement :: Parser (Either (Val, Val) Val) +statement = (Left <$> define) P.<|> (Right <$> expr) + + +------ Atoms ------ +symbol :: Parser Val +symbol = do + n <- name + when (n == "do") (unexpected "reserved word (do)") --FIXME report error position before token, not after + return $ mkSy n + +numberLit :: Parser Val +numberLit = Nm <$> anyNumber + +--TODO maybe bytes literals + +textLit :: Parser Val +textLit = do + content <- catMaybes <$> between2 (char '\"') (P.many maybeLiteralChar) + return $ mkTxt content +mkBytes = By . encodeUtf8 . T.pack +mkTxt = Tx . T.pack + +heredoc :: Parser Val +heredoc = do + string "#<<" + --grab until end of line, strip whitespace, save as `end` + --anyChar `manyThru` end + parserZero --TODO + +accessor :: Parser Val +accessor = do + key <- char ':' *> name + return $ mkCall (mkSy "__get__") (mkSy key) + + +------ Composites ------ +combine :: Parser Val +combine = do + postPadded $ char '(' + e <- bareCombination + padded $ char ')' + return e + +sq :: Parser Val +sq = do + postPadded $ char '[' + elems <- bareCombination `P.sepBy` padded comma + padded $ char ']' + return $ mkSq elems + +ob :: Parser Val +ob = do + postPadded $ char '{' + elems <- pair `P.sepBy` padded comma + padded $ char '}' + return $ mkOb elems + where + pair = do + key <- intern <$> padded name + char ':' <* whitespace + val <- bareCombination + return (key, val) + +block :: Parser Val +block = do + try $ string "do" >> whitespace + states <- P.many1 $ postPadded statement + char ';' + return $ loop states + where + loop [Left d] = mkCall (mkDefn d) (mkOb []) + loop [Right e] = e + loop (Left d:rest) = mkCall (mkDefn d) (loop rest) + loop (Right e:rest) = mkCall (mkExpr e) (loop rest) + +quote :: Parser Val +quote = do + char '`' + e <- expr + return $ mkCall (mkSy "__quote__") e + + +------ Space ------ +whitespace :: Parser () +whitespace = ( "space") . P.skipMany1 $ P.choice [spaces1, lineComment, blockComment] + +lineComment :: Parser () +lineComment = void $ do + try $ char '#' >> P.notFollowedBy (string "<<") + anyChar `manyThru` (void (char '\n') P.<|> eof) + +blockComment :: Parser () +blockComment = parserZero + +padded :: Parser a -> Parser a +padded p = try $ P.optional whitespace >> p +postPadded :: Parser a -> Parser a +postPadded p = p <* P.optional whitespace + + +------ Helpers ------ +name :: Parser String +name = P.choice [ (:) <$> namehead <*> nametail + , (:) <$> char '-' <*> P.option [] ((:) <$> (namehead P.<|> char '-') <*> nametail) + ] + where + namehead = blacklistChar (`elem` reservedFirstChar) + nametail = P.many $ blacklistChar (`elem` reservedChar) + reservedChar = "#\\\"`()[]{}:;.," + reservedFirstChar = reservedChar ++ "-0123456789" + +comma :: Parser () +comma = char ',' >> whitespace + +bareCombination :: Parser Val +bareCombination = loop <$> P.many1 (postPadded expr) + where + loop [e] = e + loop [f, x] = mkCall f x + loop es = mkCall (loop $ init es) (last es) + +mkDefn (x, val) = mkCall (mkCall (mkSy "__let__") x) val +mkExpr e = mkCall (mkCall (mkSy "__let__") (mkOb [])) e + + + diff --git a/Octopus/Primitive.hs b/Octopus/Primitive.hs new file mode 100644 --- /dev/null +++ b/Octopus/Primitive.hs @@ -0,0 +1,214 @@ +module Octopus.Primitive ( + resolveSymbol + + , match + , ifz + + , eq, neq, lt, gt, lte, gte + + , add, sub, mul, div--, quo, rem, quorem + + , numer, denom, numParts + + --TODO float arithmetic (exp, log, ln, trig) + + --, read, write, flush, close + + --, newTag + + , len, cat, cut + + , get, keys, extend, delete + + --, new, deref, assign + + --, newArr, getIx, setIx + + --TODO os interface (perhaps in a separate file) + ) where + +import Prelude hiding (div, rem) +import Import hiding (delete) +import qualified Data.Sequence as Seq +import qualified Data.Map as Map +import qualified Data.Text as T +import qualified Data.ByteString as BS + +import Octopus.Data +import Octopus.Shortcut +import Octopus.Basis + + +------ Internals ------ +{-| Lookup symbol in a value, if the binding exists. -} +resolveSymbol :: Symbol -> Val -> Maybe Val +resolveSymbol sy (Ob ob) = Map.lookup sy ob +resolveSymbol _ _ = Nothing + + +------ Non-data Primitives ------ +{-| Create a new environment by matching the second value + to atoms in the first, even if those atoms are nested + under sequences or objects. Symbols match any value and + perform binding. +-} +match :: Val -> Val -> Fallible Val +--FIXME disallow double-binding +match var val = mkOb <$> go var val + where + go :: Val -> Val -> Fallible [(Symbol, Val)] + go (Sy x) v = Right [(x, v)] + go (Sq ps) (Sq xs) | Seq.length ps == Seq.length xs = do + concat <$> mapM (uncurry go) (zip (toList ps) (toList xs)) + | otherwise = error "raise pattern match failure" + go (Sq ps) _ = Left (error "TODO") + go (Ob ps) _ | length (Map.keys ps) == 0 = Right [] + go (Ob ps) (Ob vs) = goObj (Map.toList ps) vs + where + goObj :: [(Symbol, Val)] -> Map Symbol Val -> Fallible [(Symbol, Val)] + goObj [] _ = Right [] + goObj ((k, v):ks) vs = case Map.lookup k vs of + Just v' -> (++) <$> go v v' <*> goObj ks vs + Nothing -> error "raise pattern match failure" + go pat val = error $ "unimplemented pattern-matching:\n" ++ show pat ++ "\n" ++ show val + +ifz :: Val -> Val -> Val -> Val +ifz (Nm x) | x == 0 = const + | otherwise = ignore +ifz _ = ignore +ignore x y = y + + +------ Relational ------ +eq :: Val -> Val -> Fallible Val +eq (Nm a) (Nm b) = Right . mkInt $ if a == b then 1 else 0 +eq _ _ = error "TODO eq" + +neq :: Val -> Val -> Fallible Val +neq (Nm a) (Nm b) = Right . mkInt $ if a == b then 1 else 0 +neq _ _ = error "TODO neq" + +lt :: Val -> Val -> Fallible Val +lt (Nm a) (Nm b) = Right . mkInt $ if a < b then 1 else 0 + +lte :: Val -> Val -> Fallible Val +lte (Nm a) (Nm b) = Right . mkInt $ if a <= b then 1 else 0 + +gt :: Val -> Val -> Fallible Val +gt (Nm a) (Nm b) = Right . mkInt $ if a > b then 1 else 0 + +gte :: Val -> Val -> Fallible Val +gte (Nm a) (Nm b) = Right . mkInt $ if a >= b then 1 else 0 + + +------ Arithmetic ------ +add :: Val -> Val -> Fallible Val +add (Nm a) (Nm b) = Right . Nm $ a + b +add _ _ = Left (error "TODO") + +sub :: Val -> Val -> Fallible Val +sub (Nm a) (Nm b) = Right . Nm $ a - b +sub _ _ = Left (error "TODO") + +mul :: Val -> Val -> Fallible Val +mul (Nm a) (Nm b) = Right . Nm $ a * b +mul _ _ = Left (error "TODO") + +div :: Val -> Val -> Fallible Val +div (Nm a) (Nm b) = Right . Nm $ a / b +div _ _ = Left (error "TODO") + +--quo :: Val -> Val -> Maybe Val +--quo = error "TODO" + +--rem :: Val -> Val -> Maybe Val +--rem = error "TODO" + +--quorem :: Val -> Val -> Maybe Val +--quorem = error "TODO" + + +------ Rationals ------ +numer :: Val -> Fallible Val +numer (Nm n) = Right . mkInt $ numerator n +numer _ = Left (error "TODO") + +denom :: Val -> Fallible Val +denom (Nm n) = Right . mkInt $ denominator n +denom _ = Left (error "TODO") + +trunc :: Val -> Fallible Val +trunc (Nm n) = Right . mkInt $ truncate n +trunc _ = Left (error "TODO") + +numParts :: Val -> Fallible Val +numParts (Nm n) = let (whole, frac) = properFraction n + in Right $ mkSq [mkInt whole, Nm frac] +numParts _ = Left (error "TODO") + + +------ Floats ------ + + +------ Sequence/Text/Bytes ------ +len :: Val -> Fallible Val +len (Sq xs) = Right . mkInt $ Seq.length xs +len (Tx xs) = Right . mkInt $ T.length xs +len (By xs) = Right . mkInt $ BS.length xs +len _ = Left (error "TODO") + +cat :: Val -> Val -> Fallible Val +cat (Sq xs) (Sq ys) = Right . Sq $ xs <> ys +cat (Tx xs) (Tx ys) = Right . Tx $ xs <> ys +cat (By xs) (By ys) = Right . By $ xs <> ys +cat _ _ = Left (error "TODO") + +cut :: Val -> Val -> Fallible Val --FIXME I guess I really need to return (Either Val Val), where the left is an exception to raise +cut x (Nm q) = + case x of + Sq xs -> do + i <- n + when (i >= Seq.length xs) $ Left (error "TODO") + let (as, bs) = Seq.splitAt i xs + Right $ mkSq [Sq as, Sq bs] + Tx xs -> do + i <- n + when (i >= T.length xs) $ Left (error "TODO") + let (as, bs) = T.splitAt i xs + Right $ mkSq [Tx as, Tx bs] + By xs -> do + i <- n + when (i >= BS.length xs) $ Left (error "TODO") + let (as, bs) = BS.splitAt i xs + Right $ mkSq [By as, By bs] + where + n = if denominator q == 1 then Right (fromIntegral $ numerator q) else Left (error "TODO") + + +------ Xons ------ +{-| @get x f@ retrieves field @f@ from @x@, if the field exists. -} +get :: Val -> Val -> Fallible Val +get (Ob ob) (Sy sy) = maybe (Left (error "TODO")) Right $ Map.lookup sy ob +get _ _ = Left (error "TODO") + +{-| Get a list of the fields in a value. -} +keys :: Val -> Fallible Val +keys (Ob ob) = Right . mkSq $ Sy <$> Map.keys ob +keys _ = Right $ mkSq [] + +{-| @extend a b@ extends and overwrites bindings in @b@ with bindings in @a@. -} +extend :: Val -> Val -> Val +extend (Ob ob') (Ob ob) = Ob $ Map.union ob' ob +extend _ (Ob ob) = (Ob ob) +extend (Ob ob') _ = Ob ob' +extend _ _ = mkOb [] + +{-| @delete x f@ removes field @f@ from @x@, if the field exists. + If it does not exist, then there is no change. +-} +delete :: Val -> Val -> Fallible Val +delete (Ob ob) (Sy sy) = Right . Ob $ Map.delete sy ob +delete x _ = Right x + + + diff --git a/Octopus/Shortcut.hs b/Octopus/Shortcut.hs new file mode 100644 --- /dev/null +++ b/Octopus/Shortcut.hs @@ -0,0 +1,25 @@ +module Octopus.Shortcut where + +import Import +import qualified Data.Sequence as Seq +import qualified Data.Map as Map + +import Octopus.Data + + +mkInt :: Integral a => a -> Val +mkInt = Nm . fromIntegral + +mkSy :: String -> Val +mkSy = Sy . intern + +mkSq :: [Val] -> Val +mkSq = Sq . Seq.fromList + +mkOb :: [(Symbol, Val)] -> Val +mkOb = Ob . Map.fromList + + +fromEnv :: Val -> Map Symbol Val +fromEnv (Ob ob) = ob +fromEnv _ = Map.empty diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/main.hs b/main.hs new file mode 100644 --- /dev/null +++ b/main.hs @@ -0,0 +1,94 @@ +import System.IO +import System.Environment +import System.Exit +import Control.Applicative +import Control.Concurrent.MVar + +import Octopus +import Octopus.Parser +import Octopus.Libraries + +import qualified Data.Map as Map + +main :: IO () +main = do + --parse_e <- parseOctopusFile "foo.oct" <$> readFile "test/foo.oct" + --case parse_e of + -- Left err -> print err + -- Right val -> do + -- print val + -- print =<< eval startData val + --exitSuccess + + test "do four: 4 ((vau x x) four);" + test "do four: 4 ((vau x (__eval__ x)) four);" + test "((vau [e, ast] e) dne)" + test "((vau [e, ast] ast) dne)" + test "(__extends__ [{a: 3}, {a: 2}, {a: 1}])" + test "((vau [e, ast] (__eval__ [__extends__ [{five: 5}, e], ast])) five)" + test "do four: 4 (vau [{}, ob] (__keys__ ob) {foo: 3, bar: four});" + test "do four: 4 ((vau [e, ob] (:x ob)) {x: four});" + test "do four: 4 ((vau [e, ob] (__eval__ [e, :x ob])) {x: four});" + test $ "do four: 4 (" ++ lambda ++ " ob (:x ob) {x: four});" + test $ "(" ++ lambda ++ " eight eight 8)" + test $ "("++letin++" eight 8 eight)" + + test $ "("++lambda++" let 2 "++letin++")" + test $ "("++lambda++" let (let x 2 x) "++letin++")" + test $ "("++lambda++" lambda 2 "++lambda++")" + test $ "("++lambda++" lambda (lambda x x 2) "++lambda++")" + test "(__let__ let __let__ (let x 3 x))" + test "(__let__ let __let__ (let x let (x y 3 y)))" + test "(__let__ let __let__ (let x let (x x 3 x)))" + test "(__lambda__ x x 7)" + test "(__lambda__ \955 (\955 x 7 \955) __lambda__)" + test "(__let__ \955 __lambda__ (\955 x (\955 x x) 2 7))" + test "((__lambda__ __\955__ ((__\955__ \955 ((\955 x x) 7)) __\955__)) __lambda__)" + + --TODO MAYBE this stuff could be the real definitions of let/lambda, but I've already got them built-in to the start environment (__let__ for good reason) + --test $ "("++lambda++" __\955__ (__\955__ \955 2) "++lambda++")" + --test $ "("++lambda++" __\955__ (__\955__ \955 2 __\955__) "++lambda++")" + --test $ "("++lambda++" __let__ (__let__ let __let__ 2) "++letin++")" + test $ "("++letin++" let "++letin++" (let x 2 x))" + test "[__lambda__ x x 3, __lambda__ y y 4]" --[3, 4] + + test "do \955: __lambda__\n x: 1 \n (\955 x x 3)\n y: 2\n [x, y];" --[1, 2] + test "(__del__ [{x: 1, y: 2}, `y])" + test "do \955: __lambda__\n\ + \ delete: (\955 ob (vau [{}, field] (__del__ [ob, field])))\n\ + \ (delete {x: 1, y: 2} x);" + test "do x: do \955: __lambda__\n\ + \ (\955 y y 3);\n\ + \ x;" + test "do defx: (__let__ x)\n\ + \ (defx 5 x);" + test "do defx5: (__let__ x 5)\n\ + \ (defx5 x);" + test "do [a, b, c]: [`there, `Bob, `hi] [c, a, b];" + + test "do x: (__add__ [1, 2])\n y: (__sub__ [1, 2])\n z: (__mul__ [2, 3])\n w: (__div__ [2, 3])\n [x, y, z, w];" + test "do [a, b]: (__cut__ [[1, 2, 3, 4, 5], 3])\n [a, b, __len__ a];" + test "do [a, b]: (__cut__ [\"hello\", 3])\n [a, b, __len__ a];" + test "do y: (__ifz!__ [0, `y, `n])\n n: (__ifz!__ [1, `y, `n])\n [y, n];" + + test "do {\955: \955}: (__import__ \"./test/foo.oct\") (\955 x x 6);" + + +lambda = "(vau [{}, var] (vau [static, ast] (vau arg (__eval__ [__extends__ [__match__ [var, __eval__ arg], static], ast ]))))" +letin = "(vau [{}, x] (vau val (vau [e, body] (__eval__ [__extends__ [__match__ [x, __eval__ val], e], body]))))" + + + +--TODO +--dot-infixing as normal +--colon-infixing also desugars into a getter + +testParse input = case parseOctopusExpr "" input of + Right val -> print val + Left err -> print err +test input = do + putStr $ input ++ " ===> " + cache <- newMVar Map.empty + case parseOctopusExpr "repl" input of + Right val -> print =<< eval cache startData val + Left err -> print err diff --git a/octopus.cabal b/octopus.cabal new file mode 100644 --- /dev/null +++ b/octopus.cabal @@ -0,0 +1,52 @@ +-- Initial octopus.cabal generated by cabal init. For further +-- documentation, see http://haskell.org/cabal/users-guide/ + +name: octopus +version: 0.0.1.0 +synopsis: A 100-year language inspired by Kernel, JSON, Clojure, Arc and science. +description: Octopus is a highly dynamic programming language with an astounding (I think) + power-to-weight ratio (expressivity-to-complexity). With just a handful of + simple primitives, Octopus provides a complete programming environment. Its + main focus is on complete programmer control, not on performance or static + analysis. While the user can shoot themselves, the most natural methods will + be the most reasonable. +homepage: https://github.com/Zankoku-Okuno/octopus/ +license: GPL-3 +license-file: LICENSE +author: Zankoku Okuno +maintainer: zankoku.okuno@gmail.com +-- copyright: +category: Language +build-type: Simple +cabal-version: >=1.8 + +library + exposed-modules: Octopus, + Octopus.Data, + Octopus.Shortcut + Octopus.Parser, + Octopus.Basis, + Octopus.Primitive, + Octopus.Libraries + build-depends: base ==4.6.*, + bytestring ==0.10.*, + text ==0.11.*, + containers ==0.5.*, + array ==0.4.*, + symbol ==0.2.1, + mtl ==2.1.*, + parsec ==3.1.*, + hexpr ==0.0.0.0 + +executable octopus + main-is: main.hs + -- other-modules: + build-depends: base ==4.6.*, + bytestring ==0.10.*, + text ==0.11.*, + containers ==0.5.*, + array ==0.4.*, + symbol ==0.2.1, + mtl ==2.1.*, + parsec ==3.1.*, + hexpr ==0.0.0.0