use liftA2 to merge parsers

[pdns-pipe-nmc.git] / NmcDom.hs

diff --git a/NmcDom.hs b/NmcDom.hs
index 3b8f06018f039e69e324c40a48055be4386bf6cb..8bfb6f358bde32dbcf037ee59b77f97c978f904e 100644 (file)
--- a/NmcDom.hs
+++ b/NmcDom.hs
@@ -9,7 +9,7 @@ module NmcDom   ( NmcDom(..)
                 ) where
 
 import Prelude hiding (length)
-import Control.Applicative ((<$>), (<*>), empty, pure)
+import Control.Applicative ((<$>), (<*>), liftA2, empty, pure)
 import Data.Char
 import Data.Text (Text, unpack)
 import Data.List (union)
@@ -71,15 +71,16 @@ makeMx o =
     Just _ -> empty
 
 makeSubmap :: Object -> Parser (Maybe (Map String NmcDom))
-makeSubmap o = ((.).(.)) merge merge <$> takeTls o <*> takeSrv o <*> takeMap o
+makeSubmap o = takeTls o `fmerge` takeSrv o `fmerge` takeMap o
+  where fmerge = liftA2 merge
 
 takeMap :: Object -> Parser (Maybe (Map String NmcDom))
 takeMap o =
   case H.lookup "map" o of
     Nothing          -> pure Nothing
     Just (Object mo) -> do
-      unsplit <- (parseJSON (Object mo) :: Parser (Maybe (Map String NmcDom)))
-      let result = fmap splitup unsplit
+      raw <- (parseJSON (Object mo) :: Parser (Maybe (Map String NmcDom)))
+      let result = fmap splitup raw
       return result
         where
           splitup :: Map String NmcDom -> Map String NmcDom
@@ -87,12 +88,12 @@ takeMap o =
           stow fqdn sdom acc = M.insertWith merge fqdn' sdom' acc
             where
               (fqdn', sdom') = nest (filter (/= "") (splitOnDots fqdn), sdom)
-              splitOnDots s = splitOn "." s
-              nest ([], v)   = (fqdn, v) -- can split result be empty?
+              splitOnDots s  = splitOn "." s
+              nest ([], v)   = (fqdn, v) -- preserve "self" map entry
               nest ([k], v)  = (k, v)
               nest (k:ks, v) =
                 nest (ks, def { domSubmap = Just (M.singleton k v) })
-    _                -> empty
+    _ -> empty
 
 takeSrv :: Object -> Parser (Maybe (Map String NmcDom))
 takeSrv o =