lib/Hcompta/Model/Account.hs

   1 {-# LANGUAGE DeriveDataTypeable #-}
   2 module Hcompta.Model.Account where
   3
   4 import Data.Data
   5 import Data.Function (on)
   6 import qualified Data.List
   7 import qualified Data.Map
   8 import           Data.Map (Map)
   9 import Data.Maybe (fromMaybe)
  10 import Data.Typeable ()
  11
  12 -- import qualified Hcompta.Model.Account.Path as Path
  13 import qualified Hcompta.Model.Amount       as Amount
  14 import           Hcompta.Model.Amount (Amount)
  15 import qualified Hcompta.Model.Transaction.Tag as Tag
  16 import           Hcompta.Model.Transaction.Tag (Tag)
  17
  18 -- * The 'Account' type
  19
  20 type Account = [Name]
  21 type Name = String
  22
  23 nil :: Account
  24 nil = []
  25
  26 -- | Return the given 'Account' without its last 'Name' is any.
  27 ascending :: Account -> Account
  28 ascending [] = []
  29 ascending [a] = []
  30 ascending (n:a) = n:ascending a
  31
  32 -- | Apply the given function to all the prefixes of the given 'Account'.
  33 fold :: Account -> (Account -> a -> a) -> a -> a
  34 fold = loop []
  35         where
  36                 loop :: Account -> Account -> (Account -> a -> a) -> a -> a
  37                 loop _path [] _f acc = acc
  38                 loop path (name:account) f acc =
  39                         let next = path++[name] in
  40                         loop next account f (f next acc)