Switch from pretty to ansi-wl-pprint

Nix.hs

@@ -5,8 +5,9 @@ import Nix.Eval
 import Nix.Parser
 import Nix.Pretty
 import Nix.Types
-import Text.PrettyPrint.HughesPJ 
+import Text.PrettyPrint.ANSI.Leijen
 import System.Environment
+import System.IO
 
 nix :: FilePath -> IO ()
 nix path = do
@@ -14,7 +15,7 @@ nix path = do
     case res of
         Failure e -> error $ "Parse failed: " ++ show e
         Success n -> do
-            putStrLn $ render (prettyNix n)
+            displayIO stdout $ renderPretty 0.4 80 (prettyNix n)
             top <- evalExpr n (Fix (NVSet Map.empty)) -- evaluate top level
             print top
 

Nix/Pretty.hs

@@ -1,9 +1,9 @@
 module Nix.Pretty where
 
-import Text.PrettyPrint.HughesPJ
-import Nix.Types
 import Data.Map (toList)
 import Data.Text (Text, unpack)
+import Nix.Types
+import Text.PrettyPrint.ANSI.Leijen
 
 prettyBind :: (NExpr, NExpr) -> Doc
 prettyBind (n, v) = prettyNix n <+> equals <+> prettyNix v <> semi
@@ -39,32 +39,31 @@ prettyOper (NDiv r1 r2)     = infixOper r1 "/" r2
 prettyOper (NConcat r1 r2)  = infixOper r1 "++" r2
 
 prettyAtom :: NAtom -> Doc
-prettyAtom (NStr s) = doubleQuotes $ text $ unpack $ s
+prettyAtom (NStr s) = dquotes $ text $ unpack s
 prettyAtom atom = text $ unpack $ atomText atom
 
 prettyNix :: NExpr -> Doc
 prettyNix (Fix expr) = go expr where
   go (NConstant atom) = prettyAtom atom
-  go (NOper oper) = prettyOper oper 
-  go (NList list) = lbrack <+> (fsep $ map prettyNix list) <+> rbrack
+  go (NOper oper) = prettyOper oper
+  go (NList xs) = lbracket <+> fillSep (map prettyNix xs) <+> rbracket
 
-  go (NArgSet args) = lbrace <+> (vcat $ map prettySetArg $ toList args) <+> rbrace
+  go (NArgSet args) = lbrace <+> vcat (map prettySetArg $ toList args) <+> rbrace
 
-  go (NSet rec list) = 
+  go (NSet rec xs) =
     (case rec of Rec -> "rec"; NonRec -> empty)
-    <+> lbrace <+> (vcat $ map prettyBind list) <+> rbrace
+    <+> lbrace <+> vcat (map prettyBind xs) <+> rbrace
 
-  go (NLet binds body) = text "let"
+  go (NLet _binds _body) = text "let"
   go (NIf cond trueBody falseBody) =
     (text "if" <+> prettyNix cond)
-    $$ (text "then" <+> prettyNix trueBody)
-    $$ (text "else" <+> prettyNix falseBody)
+    <$$> (text "then" <+> prettyNix trueBody)
+    <$$> (text "else" <+> prettyNix falseBody)
 
   go (NWith scope body) = text "with" <+> prettyNix scope <> semi <+> prettyNix body
   go (NAssert cond body) = text "assert" <+> prettyNix cond <> semi <+> prettyNix body
-  go (NInherit attrs) = text "inherit"
+  go (NInherit _attrs) = text "inherit"
 
   go (NVar e) = prettyNix e
   go (NApp fun arg) = prettyNix fun <+> parens (prettyNix arg)
-  go (NAbs args body) = (prettyNix args <> colon) $$ prettyNix body
-
+  go (NAbs args body) = (prettyNix args <> colon) <$$> prettyNix body

default.nix

@@ -1,5 +1,5 @@
 { cabal, parsers, trifecta, text, ansiWlPprint, parsec, transformers
-, pretty, useParsec ? true
+, useParsec ? true
 }:
 
 cabal.mkDerivation (self: rec {
@@ -11,7 +11,6 @@ cabal.mkDerivation (self: rec {
   noHaddock = true;
   buildDepends = [
     ansiWlPprint
-    pretty
     text
     transformers
   ] ++ (if useParsec then [ parsec ] else [ parsers trifecta ]);

hnix.cabal

@@ -45,7 +45,6 @@ Library
       base                     >= 4.3          && < 5
     , ansi-wl-pprint
     , containers
-    , pretty
     , text
     , transformers
   if flag(parsec)
@@ -81,7 +80,6 @@ executable hnix
     , hnix
     , ansi-wl-pprint
     , containers
-    , pretty
     , text
     , transformers
   if flag(parsec)