refactor: clarify ledger construction a bit

Hledger/Cli/Commands/Balance.hs

@@ -120,7 +120,7 @@ balance opts args l = do
 showBalanceReport :: [Opt] -> FilterSpec -> Ledger -> String
 showBalanceReport opts filterspec l = acctsstr ++ totalstr
     where
-      l' = cacheLedger'' filterspec l
+      l' = filterLedger filterspec l
       acctsstr = unlines $ map showacct interestingaccts
           where
             showacct = showInterestingAccount l' interestingaccts

Hledger/Cli/Commands/Stats.hs

@@ -19,7 +19,7 @@ import System.IO.UTF8
 stats :: [Opt] -> [String] -> Ledger -> IO ()
 stats opts args l = do
   today <- getCurrentDay
-  putStr $ showStats opts args (cacheLedger' l) today
+  putStr $ showStats opts args (filterLedger nullfilterspec l) today
 
 showStats :: [Opt] -> [String] -> Ledger -> Day -> String
 showStats _ _ l today =

Hledger/Tests.hs

@@ -283,8 +283,8 @@ tests = TestList [
                         Right e' -> (pamount $ last $ tpostings e')
                         Left _ -> error "should not happen")
 
-  ,"cacheLedger" ~:
+  -- ,"cacheLedger" ~:
-    length (Map.keys $ accountmap $ cacheLedger journal7) `is` 15
+  --   length (Map.keys $ accountmap $ cacheLedger journal7) `is` 15
 
   ,"canonicaliseAmounts" ~:
    "use the greatest precision" ~:
@@ -657,7 +657,7 @@ tests = TestList [
 --     "next january" `gives` "2009/01/01"
 
   ,"subAccounts" ~: do
-    l <- liftM cacheLedger' sampleledger
+    l <- liftM (filterLedger nullfilterspec) sampleledger
     let a = ledgerAccount l "assets"
     map aname (ledgerSubAccounts l a) `is` ["assets:bank","assets:cash"]
 
@@ -1078,7 +1078,7 @@ journal7 = Journal
           (TOD 0 0)
           ""
 
-ledger7 = cacheLedger journal7
+ledger7 = makeLedger journal7
 
 ledger8_str = unlines
  ["2008/1/1 test           "

Hledger/Utils.hs

@@ -40,14 +40,15 @@ withLedgerDo opts args cmdname cmd = do
   t <- getCurrentLocalTime
   tc <- getClockTime
   txt <-  if creating then return "" else strictReadFile f'
-  let runcmd = cmd opts args . mkLedger opts f tc txt
+  let runcmd = cmd opts args . makeUncachedLedgerWithOpts opts f tc txt
+  -- (though commands receive an uncached ledger, their type signature is just "Ledger" for now)
   if creating
    then runcmd nulljournal
    else (runErrorT . parseLedgerFile t) f >>= either parseerror runcmd
     where parseerror e = hPutStrLn stderr e >> exitWith (ExitFailure 1)
 
-mkLedger :: [Opt] -> FilePath -> ClockTime -> String -> Journal -> Ledger
+makeUncachedLedgerWithOpts :: [Opt] -> FilePath -> ClockTime -> String -> Journal -> UncachedLedger
-mkLedger opts f tc txt j = nullledger{journal=j'}
+makeUncachedLedgerWithOpts opts f tc txt j = nullledger{journal=j'}
     where j' = (canonicaliseAmounts costbasis j){filepath=f,filereadtime=tc,jtext=txt}
           costbasis=CostBasis `elem` opts
 
@@ -56,7 +57,7 @@ ledgerFromStringWithOpts :: [Opt] -> String -> IO Ledger
 ledgerFromStringWithOpts opts s = do
     tc <- getClockTime
     j <- journalFromString s
-    return $ mkLedger opts "" tc s j
+    return $ makeUncachedLedgerWithOpts opts "" tc s j
 
 -- -- | Read a Ledger from the given file, or give an error.
 -- readLedgerWithOpts :: [Opt] -> [String] -> FilePath -> IO Ledger

hledger-lib/Hledger/Data/IO.hs

@@ -6,7 +6,7 @@ Utilities for doing I/O with ledger files.
 module Hledger.Data.IO
 where
 import Control.Monad.Error
-import Hledger.Data.Ledger (cacheLedger', nullledger)
+import Hledger.Data.Ledger (makeLedger)
 import Hledger.Data.Parse (parseLedger)
 import Hledger.Data.Types (FilterSpec(..),WhichDate(..),Journal(..),Ledger(..))
 import Hledger.Data.Utils (getCurrentLocalTime)
@@ -68,7 +68,7 @@ readLedger f = do
   t <- getClockTime
   s <- readFile f
   j <- journalFromString s
-  return $ cacheLedger' $ nullledger{journal=j{filepath=f,filereadtime=t,jtext=s}}
+  return $ makeLedger j{filepath=f,filereadtime=t,jtext=s}
 
 -- -- | Read a ledger from this file, filtering according to the filter spec.,
 -- -- | or give an error.
@@ -76,8 +76,8 @@ readLedger f = do
 -- readLedgerWithFilterSpec fspec f = do
 --   s <- readFile f
 --   t <- getClockTime
---   rl <- journalFromString s
+--   j <- journalFromString s
---   return $ filterAndCacheLedger fspec s rl{filepath=f, filereadtime=t}
+--   return $ filterLedger fspec s j{filepath=f, filereadtime=t}
 
 -- | Read a Journal from the given string, using the current time as
 -- reference time, or give a parse error.

hledger-lib/Hledger/Data/Ledger.hs

@@ -78,22 +78,15 @@ nullledger = Ledger{
     }
 
 -- | Convert a journal to a more efficient cached ledger, described above.
-cacheLedger :: Journal -> Ledger
+makeLedger :: Journal -> Ledger
-cacheLedger j = nullledger{journal=j,accountnametree=ant,accountmap=amap}
+makeLedger j = nullledger{journal=j,accountnametree=ant,accountmap=amap} where (ant, amap) = crunchJournal j
-    where (ant, amap) = crunchJournal j
 
--- | Add (or recalculate) the cached journal info in a ledger.
+-- | Filter and re-cache a ledger.
-cacheLedger' :: Ledger -> CachedLedger
+filterLedger :: FilterSpec -> Ledger -> Ledger
-cacheLedger' l = l{accountnametree=ant,accountmap=amap}
+filterLedger filterspec l@Ledger{journal=j} = l{journal=j',accountnametree=ant,accountmap=amap}
-    where (ant, amap) = crunchJournal $ journal l
-
--- | Like cacheLedger, but filtering the journal first.
-cacheLedger'' filterspec l@Ledger{journal=j} = l{journal=j',accountnametree=ant,accountmap=amap}
     where (ant, amap) = crunchJournal j'
           j' = filterJournalPostings filterspec{depth=Nothing} j
 
-type CachedLedger = Ledger
-
 -- | List a ledger's account names.
 ledgerAccountNames :: Ledger -> [AccountName]
 ledgerAccountNames = drop 1 . flatten . accountnametree

hledger-lib/Hledger/Data/Types.hs

@@ -137,6 +137,10 @@ data Ledger = Ledger {
       accountmap :: Map.Map AccountName Account
     } deriving Typeable
 
+-- | An incomplete ledger, containing just the journal. Currently just a
+-- visual indicator used in a few places.
+type UncachedLedger = Ledger
+
 -- | A generic, pure specification of how to filter transactions/postings.
 -- This exists to keep app-specific options out of the hledger library.
 data FilterSpec = FilterSpec {