implemented 'delete' for hosts utility

2 files changed, 14 insertions, 7 deletions

diff --git a/Hosts.hs b/Hosts.hs
index 8d02cc3..5f09de1 100644
--- a/Hosts.hs
+++ b/Hosts.hs
@@ -9,6 +9,7 @@ module Hosts
     , assignName
     , assignName'
     , assignNewName
+    , removeName
     , inet_pton
     , inet_ntop 
     , empty
@@ -184,7 +185,18 @@ cannonizeName name line = scrubName f line
     f ws = [name," "] ++ pre ++ drop 2 rst
       where
         (pre,rst) = break (==name) ws
+
+removeName name hosts = hosts'
+ where
+    hosts' = scrubTrailingEmpties (maybe hosts (removeName0 name hosts) ns)
+    ns = Map.lookup name (namenum hosts) 
+
         
+removeName0 name hosts nums = hosts 
+    { namenum = Map.delete name (namenum hosts)
+    , numline = foldl' scrub (numline hosts) nums
+    }
+    where scrub m num = Map.adjust (scrubName $ filter (/=name)) num m
 
 assignName' :: Bool -> SockAddr -> L.ByteString -> Hosts -> Hosts
 assignName' iscannon addr name hosts = hosts'
@@ -198,7 +210,7 @@ assignName' iscannon addr name hosts = hosts'
                               else hosts { numline = foldl' canonize (numline hosts) $ fromJust ns}
          else 
             let hosts0 = -- remove name if it's present
-                         scrubTrailingEmpties $ maybe hosts (removeName hosts) ns
+                         scrubTrailingEmpties $ maybe hosts (removeName0 name hosts) ns
                 ns' = fmap (filter $
                                 isLonerName
                                 . fromJust
@@ -212,11 +224,6 @@ assignName' iscannon addr name hosts = hosts'
                                (appendName iscannon name hosts0)
                                a
             in hosts1
-    removeName hosts nums = hosts 
-        { namenum = Map.delete name (namenum hosts)
-        , numline = foldl' scrub (numline hosts) nums
-        }
-        where scrub m num = Map.adjust (scrubName $ filter (/=name)) num m
     newLine hosts = hosts
         { lineCount = cnt
         , numline = Map.insert cnt line $ numline hosts
diff --git a/hosts.hs b/hosts.hs
index 6c93b10..b73ecb3 100644
--- a/hosts.hs
+++ b/hosts.hs
@@ -65,7 +65,7 @@ grokPairing :: Bool -> Hosts -> (String,Either String SockAddr) -> Hosts
 grokPairing bCanon hosts (name,eaddr) =
     case eaddr of
         Right addr -> assignName' bCanon addr (L.pack name) hosts
-        Left "delete" -> error "deletion not implemented."
+        Left "delete" -> removeName (L.pack name) hosts
 
 main = do
     args <- getArgs