main and tests

app/Main.hs

@@ -1,4 +1,65 @@
 module Main where
 
+import Control.Monad
+import Control.Monad.Except
+
+import Data.Text    as Text
+import Data.Text.IO as Text
+
+import System.Environment
+import System.Exit
+
+import Inference
+import Inference.Env
+import Error
+import Syntax
+import Print
+import Evaluation
+
+data Command
+  = Check [FilePath]
+  | Eval  [FilePath]
+
+parseFiles :: (MonadIO m, MonadError Error m) => [FilePath] -> m [Top]
+parseFiles fs = do
+  ts <- liftIO $ mapM Text.readFile fs
+  Prelude.concat <$> mapM parse ts
+
+parseArgs :: (MonadIO m) => [String] -> m Command
+parseArgs ("check" : fs) = return $ Check fs
+parseArgs ("eval"  : fs) = return $ Eval fs
+parseArgs _              = do
+  liftIO $ putDocW 80 "usage: aleph-exe <eval | check> [files]"
+  liftIO $ exitFailure
+
 main :: IO ()
-main = putStrLn "Hello World\n"
+main = do
+  args <- getArgs
+  cmd  <- parseArgs args
+  case cmd of
+    Check fs -> do
+      errs <- runExceptT $ parseFiles fs
+      ps <- reportAndExit errs
+      t <- typecheck ps
+      liftIO $ putDocW 80 $ pretty t
+    Eval fs  -> do
+      errs <- runExceptT $ parseFiles fs
+      ps <- reportAndExit errs
+      typecheck ps
+      (e, res) <- eval ps
+      case e of
+        Just e  -> liftIO $ putDocW 80 $ pretty e <> line
+        Nothing -> liftIO $ putDocW 80 $ "Program finished successfully" <> line
+      liftIO $ putDocW 80 $ "Results:" 
+        <+> indent 2 (align $ vsep (fmap pretty res)) <> line <> line
+
+reportAndExit :: (MonadIO m) => Either Error a -> m a
+reportAndExit (Left e) = do
+  liftIO $ putDocW 80 $ pretty e <> line
+  liftIO $ exitFailure
+reportAndExit (Right v) = return v
+
+typecheck :: [Top] -> (MonadIO m) => m Env
+typecheck p = do
+  e <- runExceptT $ check p
+  reportAndExit e

test/Spec.hs

@@ -3,8 +3,6 @@
   , OverloadedStrings
 #-}
 
-import Control.Lens
-
 import Control.Monad
 import Control.Monad.Except