1 files changed, 31 insertions, 2 deletions

diff --git a/src/Network/Tox/Crypto/Transport.hs b/src/Network/Tox/Crypto/Transport.hs
index 6e2ab60b..2c13e168 100644
--- a/src/Network/Tox/Crypto/Transport.hs
+++ b/src/Network/Tox/Crypto/Transport.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                #-}
 {-# LANGUAGE DataKinds          #-}
 {-# LANGUAGE FlexibleInstances  #-}
 {-# LANGUAGE GADTs              #-}
@@ -43,8 +44,10 @@ module Network.Tox.Crypto.Transport
     , HasMessage(..)
     , HasMessageType(..)
     -- lenses
+#ifdef VERSION_lens
     , groupNumber, groupNumberToJoin, peerNumber, messageNumber
     , messageName, messageData, name, title, message, messageType
+#endif
     -- constructor
     -- utils
     , sizedN
@@ -77,7 +80,8 @@ import Data.Monoid
 import Data.Word
 import Data.Bits
 import Crypto.Hash
-import Control.Lens
+import Data.Functor.Contravariant
+import Data.Functor.Identity
 import Data.Text as T
 import Data.Text.Encoding as T
 import Data.Serialize as S
@@ -284,8 +288,10 @@ putCryptoMessage seqno (Pkt t :=> Identity x) = do
     putPacket seqno x
 
 
+#ifdef VERSION_lens
 erCompat :: String -> a
 erCompat lens = error $ "Use of '" ++ lens ++ "'  lens on incompatible CryptoMessage type"
+#endif
 
 
 newtype GroupChatId = GrpId ByteString -- 33 bytes
@@ -330,8 +336,10 @@ instance HasGroupChatID CryptoMessage where
     setGroupChatID _ _= error "setGroupChatID on non-groupchat message."
 -}
 
+#ifdef VERSION_lens
 groupChatID :: (Functor f, HasGroupChatID x) => (GroupChatId -> f GroupChatId) -> (x -> f x)
 groupChatID = lens getGroupChatID setGroupChatID
+#endif
 
 type GroupNumber = Word16
 type PeerNumber = Word16
@@ -362,8 +370,10 @@ instance HasGroupNumber CryptoMessage where
     setGroupNumber _ _ = error "setGroupNumber on CryptoMessage without group number field."
 -}
 
+#ifdef VERSION_lens
 groupNumber :: (Functor f, HasGroupNumber x) => (Word16 -> f Word16) -> (x -> f x)
 groupNumber = lens getGroupNumber setGroupNumber
+#endif
 
 class HasGroupNumberToJoin x where
     getGroupNumberToJoin :: x -> GroupNumber
@@ -384,8 +394,10 @@ instance HasGroupNumberToJoin CryptoMessage where
     setGroupNumberToJoin _ _ = error "setGroupNumberToJoin on CryptoMessage without group number (to join) field."
 -}
 
+#ifdef VERSION_lens
 groupNumberToJoin :: (Functor f, HasGroupNumberToJoin x) => (GroupNumber -> f GroupNumber) -> (x -> f x)
 groupNumberToJoin = lens getGroupNumberToJoin setGroupNumberToJoin
+#endif
 
 class HasPeerNumber x where
     getPeerNumber :: x -> PeerNumber
@@ -406,8 +418,10 @@ instance HasPeerNumber CryptoMessage where
     setPeerNumber _ _ = error "setPeerNumber on CryptoMessage without peer number field."
 -}
 
+#ifdef VERSION_lens
 peerNumber :: (Functor f, HasPeerNumber x) => (Word16 -> f Word16) -> (x -> f x)
 peerNumber = lens getPeerNumber setPeerNumber
+#endif
 
 class HasMessageNumber x where
     getMessageNumber :: x -> MessageNumber
@@ -428,9 +442,10 @@ instance HasMessageNumber CryptoMessage where
     setMessageNumber _ _ = error "setMessageNumber on CryptoMessage without message number field."
 -}
 
+#ifdef VERSION_lens
 messageNumber :: (Functor f, HasMessageNumber x) => (Word32 -> f Word32) -> (x -> f x)
 messageNumber = lens getMessageNumber setMessageNumber
-
+#endif
 
 class HasMessageName x where
     getMessageName :: x -> MessageName
@@ -453,8 +468,10 @@ instance HasMessageName CryptoMessage where
     setMessageName _ _ = error "setMessageName on CryptoMessage without message name field."
 -}
 
+#ifdef VERSION_lens
 messageName :: (Functor f, HasMessageName x) => (MessageName -> f MessageName) -> (x -> f x)
 messageName = lens getMessageName setMessageName
+#endif
 
 data KnownLossyness = KnownLossy | KnownLossless
     deriving (Eq,Ord,Show,Enum)
@@ -497,8 +514,10 @@ instance AsWord64 MessageType where
     fromWord64 x | x < 1024, x .|. 0x0200 == 0x0200 = GrpMsg (toEnum8 ((x - 512) `div` 256)) (toEnum8 x)
     fromWord64 x = error "Not clear how to convert Word64 to MessageType"
 
+#ifdef VERSION_lens
 word16 :: (Functor f, AsWord16 x) => (Word16 -> f Word16) -> (x -> f x)
 word16  = lens toWord16 (\_ x -> fromWord16 x)
+#endif
 
 instance Ord MessageType where
     compare (Msg x) (Msg y) = compare x y
@@ -540,9 +559,11 @@ instance HasMessageType CryptoData where
     setMessageType cd@(CryptoData { bufferData=bd }) typ = cd { bufferData=setMessageType bd typ }
 -}
 
+#ifdef VERSION_lens
 -- | This lens should always succeed on CryptoMessage
 messageType :: (Functor f, HasMessageType x) => (MessageType -> f MessageType) -> (x -> f x)
 messageType = lens getMessageType setMessageType
+#endif
 
 type MessageData = B.ByteString
 
@@ -568,8 +589,10 @@ instance HasMessageData CryptoMessage where
     setMessageData _ _ = error "setMessageData on CryptoMessage without message data field."
 -}
 
+#ifdef VERSION_lens
 messageData :: (Functor f, HasMessageData x) => (MessageData -> f MessageData) -> (x -> f x)
 messageData = lens getMessageData setMessageData
+#endif
 
 class HasTitle x where
     getTitle :: x -> Text
@@ -598,8 +621,10 @@ instance HasTitle CryptoMessage where
     setTitle _ _ = error "setTitle on CryptoMessage without title field."
 -}
 
+#ifdef VERSION_lens
 title :: (Functor f, HasTitle x) => (Text -> f Text) -> (x -> f x)
 title = lens getTitle setTitle
+#endif
 
 class HasMessage x where
     getMessage :: x -> Text
@@ -628,8 +653,10 @@ instance HasMessage CryptoMessage where
     setMessage _ _ = error "setMessage on CryptoMessage without message field."
 -}
 
+#ifdef VERSION_lens
 message :: (Functor f, HasMessage x) => (Text -> f Text) -> (x -> f x)
 message = lens getMessage setMessage
+#endif
 
 class HasName x where
     getName :: x -> Text
@@ -648,8 +675,10 @@ instance HasName CryptoMessage where
     setName _ _ = error "setName on CryptoMessage without name field."
 -}
 
+#ifdef VERSION_lens
 name :: (Functor f, HasTitle x) => (Text -> f Text) -> (x -> f x)
 name = lens getTitle setTitle
+#endif
 
 data PeerInfo
       = PeerInfo