mirror of
https://github.com/urbit/shrub.git
synced 2024-12-21 01:41:37 +03:00
103 lines
2.4 KiB
Haskell
103 lines
2.4 KiB
Haskell
module Data.Noun where
|
|
|
|
import Prelude hiding (all)
|
|
|
|
import Control.Applicative
|
|
import Control.Monad
|
|
import Data.Bits
|
|
import GHC.Generics
|
|
import Test.QuickCheck.Arbitrary
|
|
import Test.QuickCheck.Gen
|
|
import Data.Flat hiding (getSize)
|
|
|
|
import ClassyPrelude (Text, all, unpack)
|
|
import Data.Hashable (Hashable)
|
|
import Data.List (intercalate)
|
|
import Data.Noun.Atom (Atom)
|
|
import Data.Typeable (Typeable)
|
|
|
|
import qualified Control.Monad.Fail as Fail
|
|
import qualified Data.Char as C
|
|
|
|
|
|
-- Types -----------------------------------------------------------------------
|
|
|
|
data Cell = ACell !Noun !Noun
|
|
deriving (Eq, Ord)
|
|
|
|
data Noun
|
|
= Atom !Atom
|
|
| Cell !Noun !Noun
|
|
deriving stock (Eq, Ord, Generic)
|
|
deriving anyclass (Flat, Hashable)
|
|
|
|
data CellIdx = L | R
|
|
deriving (Eq, Ord, Show)
|
|
|
|
type NounPath = [CellIdx]
|
|
|
|
|
|
-- Instances -------------------------------------------------------------------
|
|
|
|
instance Show Noun where
|
|
show (Atom a) = show a
|
|
show (Cell x y) = fmtCell (show <$> (x : toTuple y))
|
|
where
|
|
fmtCell :: [String] -> String
|
|
fmtCell xs = "[" <> intercalate " " xs <> "]"
|
|
|
|
instance Arbitrary Noun where
|
|
arbitrary = resize 1000 go
|
|
where
|
|
dub x = Cell x x
|
|
go = do
|
|
sz <- getSize
|
|
(bit, bat :: Bool) <- arbitrary
|
|
case (sz, bit, bat) of
|
|
( 0, _, _ ) -> Atom <$> arbitrary
|
|
( _, False, _ ) -> Atom <$> arbitrary
|
|
( _, True, True ) -> dub <$> arbitrary
|
|
( _, True, _ ) -> scale (\x -> x-10) (Cell <$> go <*> go)
|
|
|
|
|
|
-- Predicates ------------------------------------------------------------------
|
|
|
|
isAtom :: Noun -> Bool
|
|
isAtom (Atom _) = True
|
|
isAtom (Cell _ _) = False
|
|
|
|
isCell :: Noun -> Bool
|
|
isCell (Atom _) = False
|
|
isCell (Cell _ _) = True
|
|
|
|
|
|
-- Tuples ----------------------------------------------------------------------
|
|
|
|
fromTuple :: [Noun] -> Noun
|
|
fromTuple [] = Atom 0
|
|
fromTuple [x] = x
|
|
fromTuple (x:xs) = Cell x (fromTuple xs)
|
|
|
|
toTuple :: Noun -> [Noun]
|
|
toTuple (Cell x xs) = x : toTuple xs
|
|
toTuple atom = [atom]
|
|
|
|
|
|
-- Lists -----------------------------------------------------------------------
|
|
|
|
fromList :: [Noun] -> Noun
|
|
fromList [] = Atom 0
|
|
fromList (x:xs) = Cell x (fromList xs)
|
|
|
|
toList :: Noun -> Maybe [Noun]
|
|
toList (Atom 0) = Just []
|
|
toList (Atom _) = Nothing
|
|
toList (Cell x xs) = (x:) <$> toList xs
|
|
|
|
example :: Noun
|
|
example = fromTuple [Atom 1337, Atom 1338, Atom 0]
|
|
|
|
exampleIO :: IO ()
|
|
exampleIO = do
|
|
print example
|