src/Compiler.hs

@@ -1,6 +1,7 @@
 module Compiler where
 
 import Eval
+import Library
 import Parser
 import Research
 
@@ -11,13 +12,8 @@ import qualified Data.Map as Map
 evaluateFile :: FilePath -> IO T
 evaluateFile filePath = do
   contents <- readFile filePath
-  let linesOfFile = lines contents
-  let env = foldl evaluateLine Map.empty linesOfFile
-  case Map.lookup "__result" env of
+  let asts = parseTricu contents
+  let finalEnv = evalTricu library asts
+  case Map.lookup "__result" finalEnv of
     Just finalResult -> return finalResult
     Nothing -> error "No result found in final environment"
-
-evaluateLine :: Env -> String -> Env
-evaluateLine env line =
-  let ast = parseSingle line
-  in evalSingle env ast

src/Eval.hs

@@ -30,33 +30,36 @@ evalSingle env term = case term of
     in Map.insert "__result" result env
 
 evalTricu :: Map String T -> [TricuAST] -> Map String T
-evalTricu env [] = env
-evalTricu env [lastLine] =
+evalTricu env list = evalTricu' env (filter (/= SEmpty) list)
+  where
+  evalTricu' :: Map String T -> [TricuAST] -> Map String T
+  evalTricu' env [] = env
+  evalTricu' env [lastLine] =
     let lastLineNoLambda = eliminateLambda lastLine
         updatedEnv = evalSingle env lastLineNoLambda
     in Map.insert "__result" (result updatedEnv) updatedEnv
-evalTricu env (line:rest) =
+  evalTricu' env (line:rest) =
     let lineNoLambda = eliminateLambda line
         updatedEnv = evalSingle env lineNoLambda
     in evalTricu updatedEnv rest
 
 evalAST :: Map String T -> TricuAST -> T
 evalAST env term = case term of
-    SVar name -> case Map.lookup name env of
-        Just value -> value
-        Nothing -> error $ "Variable " ++ name ++ " not defined"
-    TLeaf -> Leaf
-    TStem t -> Stem (evalAST env t)
-    TFork t1 t2 -> Fork (evalAST env t1) (evalAST env t2)
-    SApp t1 t2 -> apply (evalAST env t1) (evalAST env t2)
-    SStr str -> ofString str
-    SInt num -> ofNumber num
-    SList elems -> ofList (map (evalAST Map.empty) elems)
-    SEmpty -> Leaf
-    SFunc name args body ->
-        error $ "Unexpected function definition " ++ name
-        ++ " in evalAST; define via evalSingle."
-    SLambda {} -> error "Internal error: SLambda found in evalAST after elimination."
+  SVar name -> case Map.lookup name env of
+    Just value -> value
+    Nothing -> error $ "Variable " ++ name ++ " not defined"
+  TLeaf -> Leaf
+  TStem t -> Stem (evalAST env t)
+  TFork t1 t2 -> Fork (evalAST env t1) (evalAST env t2)
+  SApp t1 t2 -> apply (evalAST env t1) (evalAST env t2)
+  SStr str -> ofString str
+  SInt num -> ofNumber num
+  SList elems -> ofList (map (evalAST Map.empty) elems)
+  SEmpty -> Leaf
+  SFunc name args body ->
+    error $ "Unexpected function definition " ++ name
+    ++ " in evalAST; define via evalSingle."
+  SLambda {} -> error "Internal error: SLambda found in evalAST after elimination."
 
 eliminateLambda :: TricuAST -> TricuAST
 eliminateLambda (SLambda (v:vs) body)
@@ -117,5 +120,5 @@ tS = SApp (SApp TLeaf (SApp TLeaf (SApp (SApp TLeaf TLeaf) TLeaf))) TLeaf
 
 result :: Map String T -> T
 result r = case Map.lookup "__result" r of
-    Just a -> a
-    Nothing -> error "No __result field found in provided environment"
+  Just a -> a
+  Nothing -> error "No __result field found in provided environment"

src/Lexer.hs

@@ -104,7 +104,6 @@ tricuLexer = do
         , closeBracket
         ]
 
-
 lexTricu :: String -> [LToken]
 lexTricu input = case runParser tricuLexer "" input of
   Left err -> error $ "Lexical error:\n" ++ errorBundlePretty err

src/Library.hs

@@ -37,7 +37,7 @@ library = evalTricu Map.empty $ parseTricu $ unlines
   , "emptyList = matchList true (\\y z : false)"
   , "head = matchList t (\\hd tl : hd)"
   , "tail = matchList t (\\hd tl : tl)"
-  , "listConcat = y (\\self : matchList (\\k : k) (\\h r k : pair h (self r k)))"
+  , "lconcat = y (\\self : matchList (\\k : k) (\\h r k : pair h (self r k)))"
   , "lAnd = triage (\\x : false) (\\_ x : x) (\\_ _ x : x)"
   , "lOr = triage (\\x : x) (\\_ _ : true) (\\_ _ x : true)"
   , "hmap = y (\\self : matchList (\\f : t) (\\hd tl f : pair (f hd) (self tl f)))"

src/Main.hs

@@ -1,11 +1,11 @@
 module Main where
 
 import Compiler
-import Eval     (evalTricu, result)
+import Eval     (evalTricu, result, toAST)
 import Library  (library)
 import Parser   (parseTricu)
-import REPL     (repl)
-import Research (T)
+import REPL
+import Research
 
 import Text.Megaparsec (runParser)
 import System.Console.CmdArgs
@@ -14,7 +14,11 @@ import qualified Data.Map as Map
 
 data TricuArgs
   = Repl
-  | Compile { file :: FilePath }
+  | Compile { file :: FilePath, output :: Maybe FilePath, form :: CompiledForm }
+  | Decode { input :: Maybe FilePath }
+  deriving (Show, Data, Typeable)
+
+data CompiledForm = TreeCalculus | AST | Ternary | Ascii
   deriving (Show, Data, Typeable)
 
 replMode :: TricuArgs
@@ -24,14 +28,31 @@ replMode = Repl
   &= name "repl"
 
 compileMode :: TricuArgs
-compileMode = Compile { file = def &= typ "FILE" &= help "Relative or absolute path to compile" }
+compileMode = Compile 
+  { file = def &= typ "FILE" 
+      &= help "Relative or absolute path to file input for compilation" &= name "f"
+  , output = def &= typ "OUTPUT" 
+      &= help "Optional output file path for resulting output" &= name "o"
+  , form = TreeCalculus &= typ "FORM" 
+      &= help "Output form: (tree|ast|ternary|ascii)" 
+      &= name "t"
+  }
   &= help "Compile a file and return the result of the expression in the final line"
   &= explicit
   &= name "compile"
 
+decodeMode :: TricuArgs
+decodeMode = Decode
+  { input = def &= typ "FILE"
+            &= help "Optional file path containing a Tree Calculus value. Defaults to stdin." &= name "f"
+  }
+  &= help "Decode a Tree Calculus value into a string representation"
+  &= explicit
+  &= name "decode"
+
 main :: IO ()
 main = do
-  args <- cmdArgs $ modes [replMode, compileMode]
+  args <- cmdArgs $ modes [replMode, compileMode, decodeMode]
     &= help "tricu: Exploring Tree Calculus"
     &= program "tricu"
     &= summary "tricu - compiler and repl"
@@ -40,8 +61,23 @@ main = do
     Repl -> do
       putStrLn "Welcome to the tricu REPL"
       putStrLn "You can exit with `CTRL+D` or the `:_exit` command.`"
-      repl Map.empty
-    Compile filePath -> do
+      repl library
+    Compile { file = filePath, output = maybeOutputPath, form = form } -> do
       result <- evaluateFile filePath
-      print result
+      let fRes = formatResult form result
+      case maybeOutputPath of
+        Just outputPath -> do
+          writeFile outputPath fRes
+          putStrLn $ "Output to: " ++ outputPath
+        Nothing -> putStr fRes
+    Decode { input = maybeInputPath } -> do
+      value <- case maybeInputPath of
+        Just inputPath -> readFile inputPath
+        Nothing -> getContents
+      putStrLn $ decodeResult $ result $ evalTricu library $ parseTricu value
 
+formatResult :: CompiledForm -> T -> String
+formatResult TreeCalculus = show
+formatResult AST          = show . toAST
+formatResult Ternary      = toTernaryString
+formatResult Ascii        = toAscii

src/Parser.hs

@@ -11,7 +11,8 @@ import Text.Megaparsec.Error (errorBundlePretty, ParseErrorBundle)
 
 import qualified Data.Set as Set
 
-type Parser = Parsec Void [LToken]
+type Parser    = Parsec Void [LToken]
+type AltParser = Parsec Void String
 
 data TricuAST
   = SVar String
@@ -242,6 +243,42 @@ isLiteral _ = False
 isNewline (LNewline) = True
 isNewline _ = False
 
+-- Alternative parsers
+altSC :: AltParser ()
+altSC = skipMany (char ' ' <|> char '\t' <|> char '\n')
+
+parseTernaryTerm :: AltParser TricuAST
+parseTernaryTerm = do
+  altSC
+  term <- choice parseTernaryTerm'
+  altSC
+  pure term
+  where
+    parseTernaryTerm' =
+      [ try (between (char '(') (char ')') parseTernaryTerm)
+      , try parseTernaryLeaf
+      , try parseTernaryStem
+      , try parseTernaryFork
+      ]
+
+parseTernaryLeaf :: AltParser TricuAST
+parseTernaryLeaf = char '0' *> pure TLeaf
+
+parseTernaryStem :: AltParser TricuAST
+parseTernaryStem = char '1' *> (TStem <$> parseTernaryTerm)
+
+parseTernaryFork :: AltParser TricuAST
+parseTernaryFork = do
+  char '2'
+  term1 <- parseTernaryTerm
+  term2 <- parseTernaryTerm
+  pure $ TFork term1 term2
+
+parseTernary :: String -> Either String TricuAST
+parseTernary input = case runParser (parseTernaryTerm <* eof) "" input of
+  Left err -> Left (errorBundlePretty err)
+  Right ast -> Right ast
+
 -- Error Handling
 handleParseError :: ParseErrorBundle [LToken] Void -> String
 handleParseError bundle =
@@ -259,4 +296,3 @@ showError (FancyError offset fancy) =
 showError (TrivialError offset Nothing expected) =
   "Parse error at offset " ++ show offset ++ ": expected one of "
   ++ show (Set.toList expected)
-

src/REPL.hs

@@ -27,18 +27,18 @@ repl env = runInputT defaultSettings (loop env)
         Just input -> do
           newEnv <- liftIO $ (processInput env input `catch` errorHandler env)
           loop newEnv
-
-    processInput :: Env -> String -> IO (Env)
+  
+    processInput :: Env -> String -> IO Env
     processInput env input = do
-      let clearEnv = Map.delete "__result" env
-          newEnv = evalSingle clearEnv (parseSingle input)
+      let asts = parseTricu input
+          newEnv = evalTricu env asts
       case Map.lookup "__result" newEnv of
         Just r -> do
           putStrLn $ "tricu > " ++ show r
           putStrLn $ "READ -: \"" ++ decodeResult r ++ "\""
         Nothing -> return ()
       return newEnv
-
+    
     errorHandler :: Env -> SomeException -> IO (Env)
     errorHandler env e = do
       putStrLn $ "Error: " ++ show e

src/Research.hs

@@ -18,16 +18,6 @@ apply (Fork (Fork a1 a2) a3) Leaf       = a1
 apply (Fork (Fork a1 a2) a3) (Stem u)   = apply a2 u
 apply (Fork (Fork a1 a2) a3) (Fork u v) = apply (apply a3 u) v
 
-reduce :: T -> T
-reduce expr =
-  let next = step expr
-  in if next == expr then expr else reduce next
-
-step :: T -> T
-step (Fork left right) = reduce (apply (reduce left) (reduce right))
-step (Stem inner) = Stem (reduce inner)
-step t = t
-
 -- SKI Combinators
 _S :: T
 _S = Fork (Stem (Fork Leaf Leaf)) Leaf
@@ -88,6 +78,12 @@ toList (Fork x rest) = case toList rest of
   Left err -> Left err
 toList _ = Left "Invalid Tree Calculus list"
 
+-- Outputs
+toTernaryString :: T -> String
+toTernaryString Leaf = "0"
+toTernaryString (Stem t) = "1" ++ toTernaryString t
+toTernaryString (Fork t1 t2) = "2" ++ toTernaryString t1 ++ toTernaryString t2
+
 -- Utility
 type Env = Map.Map String T 
 

test.tri

@@ -1,2 +0,0 @@
-x = t t t
-x

test/Spec.hs

@@ -1,12 +1,15 @@
 module Main where
 
+import Compiler
 import Eval
 import Lexer
 import Library
 import Parser
 import REPL
 import Research
+
 import Control.Exception (evaluate, try, SomeException)
+import Control.Monad.IO.Class (liftIO)
 import Test.Tasty
 import Test.Tasty.HUnit
 import Test.Tasty.QuickCheck
@@ -28,6 +31,7 @@ tests = testGroup "Tricu Tests"
   , evaluationTests
   , lambdaEvalTests
   , libraryTests
+  , compilerTests
   , propertyTests
   ]
 
@@ -213,7 +217,7 @@ evaluationTests = testGroup "Evaluation Tests"
       let input = "x = t t\nx = t\nx"
           env = evalTricu Map.empty (parseTricu input)
       (result env) @?= Leaf
-    , testCase "Apply identity to Boolean Not" $ do
+  , testCase "Apply identity to Boolean Not" $ do
       let not = "(t (t (t t) (t t t)) t)"
       let input = "x = (\\a : a)\nx " ++ not
           env = evalTricu Map.empty (parseTricu input)
@@ -364,7 +368,7 @@ libraryTests = testGroup "Library Tests"
           env = evalTricu library (parseTricu input)
       result env @?= Stem Leaf
   , testCase "Concatenate strings" $ do
-      let input = "listConcat \"Hello, \" \"world!\""
+      let input = "lconcat \"Hello, \" \"world!\""
           env = decodeResult $ result $ evalTricu library (parseTricu input)
       env @?= "Hello, world!"
   , testCase "Verifying Equality" $ do
@@ -373,6 +377,19 @@ libraryTests = testGroup "Library Tests"
       result env @?= Stem Leaf
   ]
 
+compilerTests :: TestTree
+compilerTests = testGroup "Compiler tests"
+  [ testCase "Forks" $ do
+      res <- liftIO $ evaluateFile "./test/fork.tri"
+      res @?= Fork Leaf Leaf
+  , testCase "File ends with comment" $ do
+      res <- liftIO $ evaluateFile "./test/comments-1.tri"
+      res @?= Fork (Stem Leaf) Leaf
+  , testCase "Mapping and Equality" $ do
+      res <- liftIO $ evaluateFile "./test/map.tri"
+      res @?= Stem Leaf
+  ]
+
 propertyTests :: TestTree
 propertyTests = testGroup "Property Tests"
   [ testProperty "Lexing and parsing round-trip" $ \input ->

test/ascii.tri

@@ -0,0 +1 @@
+t (t (t (t (t t) (t t t)) t) t t) t

test/comments-1.tri

@@ -0,0 +1,9 @@
+-- This is a tricu comment!
+-- t (t t) (t (t t t))
+-- t (t t t) (t t)
+-- x = (\a : a)
+t (t t) t -- Fork (Stem Leaf) Leaf
+-- t t
+-- x
+-- x = (\a : a)
+-- t

test/fork.tri

@@ -0,0 +1 @@
+t t t 

test/map.tri

@@ -0,0 +1,24 @@
+false = t
+true = t t
+_ = t
+k = t t
+i = t (t k) t
+s = t (t (k t)) t
+m = s i i
+b = s (k s) k
+c = s (s (k s) (s (k k) s)) (k k)
+iC = (\a b c : s a (k c) b)
+yi = (\i : b m (c b (i m)))
+y = yi iC
+triage = (\a b c : t (t a b) c)
+pair = t
+matchList = (\oe oc : triage oe _ oc)
+lconcat = y (\self : matchList (\k : k) (\h r k : pair h (self r k)))
+hmap = y (\self : matchList (\f : t) (\hd tl f : pair (f hd) (self tl f)))
+map = (\f l : hmap l f)
+lAnd = triage (\x : false) (\_ x : x) (\_ _ x : x)
+lOr = triage (\x : x) (\_ _ : true) (\_ _ x : true)
+equal = y (\self : triage (triage true (\z : false) (\y z : false)) (\ax : triage false (self ax) (\y z : false)) (\ax ay : triage false (\z : false) (\bx by : lAnd (self ax bx) (self ay by))))
+
+x = map (\i : lconcat "Successfully concatenated " i) [("two strings!")]
+equal x [("Successfully concatenated two strings!")]