Revision 78209a84

b/src/Ganeti/BasicTypes.hs
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  _       <*> (Bad x) = Bad x
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  (Ok f)  <*> (Ok x)  = Ok $ f x
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instance (FromString a, Monoid a) => Alternative (GenericResult a) where


  		





  
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  empty = mzero


  		





  
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  (<|>) = mplus


  		





  
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-- | This is a monad transformation for Result. It's implementation is


  		





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-- based on the implementations of MaybeT and ErrorT.


  		





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newtype ResultT a m b = ResultT {runResultT :: m (GenericResult a b)}


  		





  ......




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  mplus x y = elimResultT combine return x


  		





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    where combine x' = ResultT $ liftM (mplus (Bad x')) (runResultT y)


  		





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instance (Monad m, FromString a, Monoid a) => Alternative (ResultT a m) where


  		





  
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  empty = mzero


  		





  
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  (<|>) = mplus


  		





  
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-- | Lift a `Result` value to a `ResultT`.


  		





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resultT :: Monad m => GenericResult a b -> ResultT a m b


  		





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resultT = ResultT . return


  		












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