sigma-ij-0.2: src/Math/FreeModule/PP.hs

-- | More concrete prettyprinting.
-- this should be a separated package.
 
{-# LANGUAGE TypeFamilies, FlexibleContexts, FlexibleInstances, CPP #-}
module Math.FreeModule.PP where

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import Data.Ratio

import Math.FreeModule.Class
import Math.FreeModule.Symbol
import Math.FreeModule.PrettyPrint

import qualified Math.FreeModule.SortedList as SL

import Math.Algebra.ModP

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class Pretty a where
  pretty :: a -> String
  
pp :: Pretty a => a -> IO ()
pp = putStrLn . pretty

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instance Pretty Symbol where pretty = showSymbol

--instance (Pretty b, Ord b, Real c, Show c) => Pretty (SL.FreeMod b c) where
--  pretty = bracket (prettyPrintRealWith pretty)

instance (Pretty b, Ord b) => Pretty (SL.FreeMod b Zp) where
  pretty = bracket (prettyPrintArbWith pretty showZp)

showZp :: Zp -> String
showZp (Zp n) = show n

instance (Pretty b, Ord b) => Pretty (SL.FreeMod b Integer) where
  pretty = bracket (prettyPrintRealWith' show pretty)

instance (Pretty b, Ord b) => Pretty (SL.FreeMod b Rational) where
  pretty = bracket (prettyPrintRealWith' showRational pretty)

showRational :: Rational -> String
showRational r = if denominator r == 1 
  then show (numerator r)
  else "(" ++ show (numerator r) ++ "/" ++ show (denominator r) ++ ")"
  
--------------------------------------------------------------------------------