escStr :: String -> String
escStr = concatMap (\ c -> case Map.lookup c $ Map.fromList escMap of
    Nothing -> [c]
    Just e -> ['X', e])
escStr :: String -> String
escStr = concatMap (\ c -> case Map.lookup c $ Map.fromList escMap of
    Nothing -> [c]
    Just e -> ['X', e])
escStr = concatMap (\ c -> case Map.lookup c $ Map.fromList escMap of
    Nothing -> [c]
    Just e -> ['X', e])