Minimum usable: configurator

There are many great Haskell libraries. But usually it will take equally great amount of effort for people to get familiar with them.
Worstly, it seems like some examples were designed to bring more obstracle deliberately. Package section follows the minimum usable principle. Examples of this section is clear enough for reminding myself in future. Hopefully, it will also offer some help to others.

online resouces:

1. store
2. cereal
   

Notes

Both packages can be used the same ways 1. GHC extension

>  {-# LANGUAGE DeriveGeneric #-}            
>  {-# LANGUAGE DefaultSignatures #-}                                     

1. Import corresponding libraries:
   

sore package

   import Data.Sort

cereal package

   import Data.Serialize

1. Rely on GHC.Generics

       import GHC.Generics
       ...
       data DemoMap = DemoMap    
         { toMapList :: [([String], [Float])]    
         } deriving (Generic, Show)
   

2. Declare as Instance

   store package

      instance Store DemoMap
   

   cereal package

      instance Serialization DemoMap
   

3. Write to / Read from file by Data.ByteString

store pakcage

        import qualified Data.ByteString as BL
        ...
        serializeDemoMap:: FilePath -> StandardMap -> IO ()
        serializeDemoMap filePath sdmap = BL.writeFile filePath (encode sdmap)
                                             
        deserializeDemoMap :: FilePath -> IO (Either PeekException StandardMap)
        deserializeDemoMap filePath = do          
            bs <- BL.readFile filePath              
            return $ decode bs        

cereal package

        import qualified Data.ByteString.Lazy as BL
        ...
        serializeDemoMap :: FilePath -> StandardMap -> IO ()
        serializeDemoMap filePath sdmap = BL.writeFile filePath (encodeLazy sdmap)

        deserializeDemoMap :: FilePath -> IO (Either String StandardMap)
        deserializeDemoMap filePath = do          
          bs <- BL.readFile filePath              
          return $ decodeLazy bs

1. The file produced by store is about 1/3 bigger than file produced by cereal.
2. store handles parametric data type more smoothly.
3. Performance test: TODO