haskell.hs

haskell.hs

{-# LANGUAGE TypeApplications #-}                               
{-# OPTIONS_HADDOCK show-extensions #-}                         
                                                                
module BitfinexClient.Class.BfxRound                            
  ( bfxRound,                                                   
  )                                                             
where                                                           
                                                                
import BitfinexClient.Data.Kind                                 
import BitfinexClient.Data.Metro                                
import BitfinexClient.Import.External                           
                                                                
class (From a Rational, TryFrom Rational a) => BfxRound a where 
  bfxRound' :: a -> Either (TryFromException Rational a) a      
                                                                
instance BfxRound (QuotePerBase act) where                      
  bfxRound' =                                                   
    tryFrom                                                     
      . sdRound 5                                               
      . dpRound 8                                               
      . from                                                    
                                                                
instance BfxRound (MoneyAmt dim act pre) where                  
  bfxRound' =                                                   
    tryFrom                                                     
      . dpRound 8                                               
      . from                                                    

{-
    • Couldn't match representation of type: a 'UnRounded                
                               with that of: a 'Rounded                  
        arising from a use of ‘coerce’                                   
      NB: We cannot know what roles the parameters to ‘a’ have;          
        we must assume that the role is nominal                          
    • In the first argument of ‘(.)’, namely ‘coerce’                    
      In the expression: coerce . bfxRound'                              
      In an equation for ‘bfxRound’: bfxRound = coerce . bfxRound'       
    • Relevant bindings include                                          
        bfxRound :: a 'UnRounded                                         
                    -> Either (TryFromException Rational (a 'Rounded))   
(a 'Rounded)                                                             
          (bound at /app/bitfinex-client/src/BitfinexClient/Class/BfxRoun
d.hs:35:1)                                                               
   |                                                                     
36 |   coerce                                                            
   |   ^^^^^^                                                            
-}

bfxRound ::                                                     
  forall a.                                                     
  ( BfxRound (a 'UnRounded)                                     
  ) =>                                                          
  a 'UnRounded ->                                               
  Either (TryFromException Rational (a 'Rounded)) (a 'Rounded)  
bfxRound =                                                      
  coerce                                                        
    . bfxRound'