+
+descendNmc :: [String] -> NmcDom -> NmcDom
+descendNmc subdom dom = case subdom of
+ [] ->
+ case domMap dom of
+ Nothing -> dom
+ Just map ->
+ case M.lookup "" map of -- Stupid, but "" is allowed in the map
+ Nothing -> dom -- Try to merge it with the root data
+ Just sub -> mergeNmc sub dom
+ d:ds ->
+ case domMap dom of
+ Nothing -> emptyNmcDom
+ Just map ->
+ case M.lookup d map of
+ Nothing -> emptyNmcDom
+ Just sub -> descendNmc ds sub
+
+-- FIXME -- I hope there exists a better way to merge records!
+mergeNmc :: NmcDom -> NmcDom -> NmcDom
+mergeNmc sub dom = dom { domService = choose dom domService sub
+ , domIp = choose dom domIp sub
+ , domIp6 = choose dom domIp6 sub
+ , domTor = choose dom domTor sub
+ , domI2p = choose dom domI2p sub
+ , domFreenet = choose dom domFreenet sub
+ , domAlias = choose dom domAlias sub
+ , domTranslate = choose dom domTranslate sub
+ , domEmail = choose dom domEmail sub
+ , domLoc = choose dom domLoc sub
+ , domInfo = choose dom domInfo sub
+ , domNs = choose dom domNs sub
+ , domDelegate = choose dom domDelegate sub
+ , domImport = choose dom domImport sub
+ , domFingerprint = choose dom domFingerprint sub
+ , domTls = choose dom domTls sub
+ , domDs = choose dom domDs sub
+ }
+ where
+ choose :: NmcDom -> (NmcDom -> Maybe a) -> NmcDom -> Maybe a
+ choose sub t dom = case t dom of
+ Nothing -> t sub
+ Just x -> Just x