Merge #839: Basic polymorphism refactor

Clean-up refactor, with some equivalent code simplification, some functor fusioning in executable.

Author: Anton-Latukha

main/Main.hs

@@ -55,9 +55,9 @@ main = do
     Nothing -> case expression opts of
       Just s  -> handleResult opts Nothing (parseNixTextLoc s)
       Nothing -> case fromFile opts of
-        Just "-" -> mapM_ (processFile opts) =<< (lines <$> liftIO getContents)
+        Just "-" -> mapM_ (processFile opts) . lines =<< liftIO getContents
         Just path ->
-          mapM_ (processFile opts) =<< (lines <$> liftIO (readFile path))
+          mapM_ (processFile opts) . lines =<< liftIO (readFile path)
         Nothing -> case filePaths opts of
           [] -> withNixContext Nothing Repl.main
           ["-"] ->

main/Repl.hs

@@ -348,7 +348,7 @@ completeFunc reversedPrev word
   -- Commands
   | reversedPrev == ":"
   = pure . listCompletion
-      $ map helpOptionName (helpOptions :: HelpOptions e t f m)
+      $ fmap helpOptionName (helpOptions :: HelpOptions e t f m)
 
   -- Files
   | any (`Data.List.isPrefixOf` word) [ "/", "./", "../", "~/" ]
@@ -363,9 +363,7 @@ completeFunc reversedPrev word
       Nothing -> pure []
       Just binding -> do
         candidates <- lift $ algebraicComplete subFields binding
-        pure
-          $ map notFinished
-          $ listCompletion (Data.Text.unpack . (var <>) <$> candidates)
+        pure $ notFinished <$> listCompletion (Data.Text.unpack . (var <>) <$> candidates)
 
   -- Builtins, context variables
   | otherwise
@@ -377,11 +375,11 @@ completeFunc reversedPrev word
 
     pure $ listCompletion
       $ ["__includes"]
-      ++ (Data.Text.unpack <$> contextKeys)
-      ++ (Data.Text.unpack <$> shortBuiltins)
+      <> (Data.Text.unpack <$> contextKeys)
+      <> (Data.Text.unpack <$> shortBuiltins)
 
   where
-    listCompletion = map simpleCompletion . filter (word `Data.List.isPrefixOf`)
+    listCompletion = fmap simpleCompletion . filter (word `Data.List.isPrefixOf`)
 
     notFinished x = x { isFinished = False }
 
@@ -401,7 +399,7 @@ completeFunc reversedPrev word
                   Nothing -> pure []
                   Just e ->
                     demand e
-                    (\e' -> fmap (("." <> f) <>) <$> algebraicComplete fs e')
+                      (\e' -> (fmap . fmap) (("." <> f) <>) $ algebraicComplete fs e')
 
       in case val of
         NVSet xs _ -> withMap xs
@@ -508,7 +506,7 @@ renderSetOptions :: [HelpSetOption] -> Doc ()
 renderSetOptions so =
   Prettyprinter.indent 4
     $ Prettyprinter.vsep
-    $ flip map so
+    $ flip fmap so
     $ \h ->
              Prettyprinter.pretty (helpSetOptionName h)
          <+> helpSetOptionSyntax h

src/Nix.hs

@@ -107,7 +107,7 @@ evaluateExpression
   -> m a
 evaluateExpression mpath evaluator handler expr = do
   opts :: Options <- asks (view hasLens)
-  args <- traverse (traverse eval') $ map (second parseArg) (arg opts) ++ map
+  args <- traverse (traverse eval') $ fmap (second parseArg) (arg opts) ++ fmap
     (second mkStr)
     (argstr opts)
   evaluator mpath expr >>= \f -> demand f $ \f' ->