lib/Hcompta/Amount/Unit.hs

   1 {-# LANGUAGE DeriveDataTypeable #-}
   2 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
   3 {-# LANGUAGE OverloadedStrings #-}
   4 module Hcompta.Amount.Unit where
   5
   6 import           Data.Data
   7 import           Data.String (IsString)
   8 import qualified Data.Text as Text
   9 import           Data.Text (Text)
  10 import           Data.Typeable ()
  11
  12 newtype Unit
  13  = Unit Text
  14  deriving (Data, Eq, IsString, Ord, Show, Typeable)
  15
  16 -- NOTE: maybe consider using text-show package
  17 text :: Unit -> Text
  18 text (Unit t) = t
  19
  20 nil :: Unit
  21 nil = Unit ""
  22
  23 length :: Unit -> Int
  24 length = Text.length . text