From a19a943f9b2b0f937c6fc6ce309bf425659133c9 Mon Sep 17 00:00:00 2001
From: Joe Hermaszewski <git@monoid.al>
Date: Wed, 29 Jun 2016 00:10:09 +0100
Subject: [PATCH] Derive foldable and traversable for more types

---
 Nix/Expr/Types.hs           | 20 ++++++++++++++++----
 Nix/Expr/Types/Annotated.hs |  4 +++-
 hnix.cabal                  |  2 +-
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/Nix/Expr/Types.hs b/Nix/Expr/Types.hs
index 891d809..265a198 100644
--- a/Nix/Expr/Types.hs
+++ b/Nix/Expr/Types.hs
@@ -70,7 +70,7 @@ data NExprF r
   -- evaluate the second argument.
   | NAssert !r !r
   -- ^ Assert that the first returns true before evaluating the second.
-  deriving (Ord, Eq, Generic, Typeable, Data, Functor, Show)
+  deriving (Ord, Eq, Generic, Typeable, Data, Functor, Foldable, Traversable, Show)
 
 instance Show1 NExprF where
   showsPrec1 = showsPrec
@@ -90,7 +90,7 @@ data Binding r
   | Inherit !(Maybe r) ![NKeyName r]
   -- ^ Using a name already in scope, such as @inherit x;@ which is shorthand
   -- for @x = x;@ or @inherit (x) y;@ which means @y = x.y;@.
-  deriving (Typeable, Data, Ord, Eq, Functor, Show)
+  deriving (Typeable, Data, Ord, Eq, Functor, Foldable, Traversable, Show)
 
 -- | @Params@ represents all the ways the formal parameters to a
 -- function can be represented.
@@ -119,7 +119,7 @@ data ParamSet r
 -- | 'Antiquoted' represents an expression that is either
 -- antiquoted (surrounded by ${...}) or plain (not antiquoted).
 data Antiquoted v r = Plain !v | Antiquoted !r
-  deriving (Ord, Eq, Generic, Typeable, Data, Functor, Show)
+  deriving (Ord, Eq, Generic, Typeable, Data, Functor, Foldable, Traversable, Show)
 
 -- | An 'NString' is a list of things that are either a plain string
 -- or an antiquoted expression. After the antiquotes have been evaluated,
@@ -131,7 +131,7 @@ data NString r
   | Indented ![Antiquoted Text r]
   -- ^ Strings wrapped with two single quotes ('') can contain newlines,
   -- and their indentation will be stripped.
-  deriving (Eq, Ord, Generic, Typeable, Data, Functor, Show)
+  deriving (Eq, Ord, Generic, Typeable, Data, Functor, Foldable, Traversable, Show)
 
 -- | For the the 'IsString' instance, we use a plain doublequoted string.
 instance IsString (NString r) where
@@ -173,6 +173,18 @@ instance Functor NKeyName where
   fmap f (DynamicKey (Antiquoted e)) = DynamicKey . Antiquoted $ f e
   fmap _ (StaticKey key) = StaticKey key
 
+instance Foldable NKeyName where
+  foldMap f = \case
+    DynamicKey (Plain str) -> foldMap f str
+    DynamicKey (Antiquoted e) -> f e
+    StaticKey _ -> mempty
+
+instance Traversable NKeyName where
+  sequenceA = \case
+    DynamicKey (Plain str) -> DynamicKey . Plain <$> sequenceA str
+    DynamicKey (Antiquoted e) -> DynamicKey . Antiquoted <$> e
+    StaticKey key -> pure (StaticKey key)
+
 -- | A selector (for example in a @let@ or an attribute set) is made up
 -- of strung-together key names.
 type NAttrPath r = [NKeyName r]
diff --git a/Nix/Expr/Types/Annotated.hs b/Nix/Expr/Types/Annotated.hs
index 468583d..14fa6fe 100644
--- a/Nix/Expr/Types/Annotated.hs
+++ b/Nix/Expr/Types/Annotated.hs
@@ -1,5 +1,7 @@
 {-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DeriveFunctor      #-}
+{-# LANGUAGE DeriveFoldable     #-}
+{-# LANGUAGE DeriveTraversable  #-}
 {-# LANGUAGE PatternSynonyms    #-}
 {-# LANGUAGE DeriveGeneric      #-}
 {-# LANGUAGE FlexibleInstances  #-}
@@ -38,7 +40,7 @@ data SrcSpan = SrcSpan{ spanBegin :: Delta
 data Ann ann a = Ann{ annotation :: ann
                     , annotated  :: a
                     }
-  deriving (Ord, Eq, Data, Generic, Typeable, Functor, Read, Show)
+  deriving (Ord, Eq, Data, Generic, Typeable, Functor, Foldable, Traversable, Read, Show)
 
 instance Show ann => Show1 (Ann ann) where
   showsPrec1 = showsPrec
diff --git a/hnix.cabal b/hnix.cabal
index d93a205..a895ec0 100644
--- a/hnix.cabal
+++ b/hnix.cabal
@@ -1,5 +1,5 @@
 Name:                hnix
-Version:             0.3.1
+Version:             0.3.2
 Synopsis:            Haskell implementation of the Nix language
 Description:
   Haskell implementation of the Nix language.