balance: --flat provides a simple non-hierarchical format

Hledger/Cli/Commands/Balance.hs

@@ -123,21 +123,25 @@ showBalanceReport opts filterspec j = acctsstr ++ totalstr
       l = journalToLedger filterspec j
       acctsstr = unlines $ map showacct interestingaccts
           where
-            showacct = showInterestingAccount l interestingaccts
+            showacct = showInterestingAccount opts l interestingaccts
             interestingaccts = filter (isInteresting opts l) acctnames
             acctnames = sort $ tail $ flatten $ treemap aname accttree
             accttree = ledgerAccountTree (fromMaybe 99999 $ depthFromOpts opts) l
       totalstr | NoTotal `elem` opts = ""
-               | notElem Empty opts && isZeroMixedAmount total = ""
                | otherwise = printf "--------------------\n%s\n" $ padleft 20 $ showMixedAmountWithoutPrice total
           where
             total = sum $ map abalance $ ledgerTopAccounts l
 
 -- | Display one line of the balance report with appropriate indenting and eliding.
-showInterestingAccount :: Ledger -> [AccountName] -> AccountName -> String
+showInterestingAccount :: [Opt] -> Ledger -> [AccountName] -> AccountName -> String
-showInterestingAccount l interestingaccts a = concatTopPadded [amt, "  ", depthspacer ++ partialname]
+showInterestingAccount opts l interestingaccts a = concatTopPadded [amt, "  ", name]
     where
-      amt = padleft 20 $ showMixedAmountWithoutPrice $ abalance $ ledgerAccount l a
+      amt = padleft 20 $ showMixedAmountWithoutPrice bal
+      bal | Flat `elem` opts = exclusiveBalance acct
+          | otherwise = abalance acct
+      acct = ledgerAccount l a
+      name | Flat `elem` opts = a
+           | otherwise        = depthspacer ++ partialname
       parents = parentAccountNames a
       interestingparents = filter (`elem` interestingaccts) parents
       depthspacer = replicate (indentperlevel * length interestingparents) ' '
@@ -147,9 +151,23 @@ showInterestingAccount l interestingaccts a = concatTopPadded [amt, "  ", depths
       partialname = accountNameFromComponents $ reverse (map accountLeafName ps) ++ [accountLeafName a]
           where ps = takeWhile boring parents where boring = not . (`elem` interestingparents)
 
+exclusiveBalance :: Account -> MixedAmount
+exclusiveBalance = sumPostings . apostings
+
 -- | Is the named account considered interesting for this ledger's balance report ?
 isInteresting :: [Opt] -> Ledger -> AccountName -> Bool
-isInteresting opts l a
+isInteresting opts l a | Flat `elem` opts = isInterestingFlat opts l a
+                       | otherwise = isInterestingIndented opts l a
+
+isInterestingFlat :: [Opt] -> Ledger -> AccountName -> Bool
+isInterestingFlat opts l a = notempty || emptyflag
+    where
+      acct = ledgerAccount l a
+      notempty = not $ isZeroMixedAmount $ exclusiveBalance acct
+      emptyflag = Empty `elem` opts
+
+isInterestingIndented :: [Opt] -> Ledger -> AccountName -> Bool
+isInterestingIndented opts l a
     | numinterestingsubs==1 && not atmaxdepth = notlikesub
     | otherwise = notzero || emptyflag
     where

Hledger/Cli/Options.hs

@@ -75,6 +75,7 @@ options = [
  ,Option ""    ["effective"]    (NoArg  Effective)     "use transactions' effective dates, if any"
  ,Option "E" ["empty"]        (NoArg  Empty)         "show empty/zero things which are normally elided"
  ,Option "R" ["real"]         (NoArg  Real)          "report only on real (non-virtual) transactions"
+ ,Option ""  ["flat"]         (NoArg  Flat)          "balance report: show full account names, unindented"
  ,Option ""    ["no-total"]     (NoArg  NoTotal)       "balance report: hide the final total"
 -- ,Option "s" ["subtotal"]     (NoArg  SubTotal)      "balance report: show subaccounts"
  ,Option "W" ["weekly"]       (NoArg  WeeklyOpt)     "register report: show weekly summary"
@@ -113,6 +114,7 @@ data Opt =
     Effective | 
     Empty | 
     Real | 
+    Flat |
     NoTotal |
     SubTotal |
     WeeklyOpt |

MANUAL.markdown

@@ -224,6 +224,7 @@ Here is the command-line help:
               --effective          use transactions' effective dates, if any
      -E       --empty              show empty/zero things which are normally elided
      -R       --real               report only on real (non-virtual) transactions
+              --flat               balance report: show full account names, unindented
               --no-total           balance report: hide the final total
      -W       --weekly             register report: show weekly summary
      -M       --monthly            register report: show monthly summary
@@ -274,14 +275,21 @@ Examples:
 
 ##### balance
 
-The balance command displays accounts and their balances.
+The balance command displays accounts and their balances, indented to show the account hierarchy.
-
 Examples:
 
     $ hledger balance
     $ hledger balance food -p 'last month'
+
+A final total is displayed, use `--no-total` to suppress this. Also, the
+`--depth` option shows accounts only to the specified depth, useful for an overview:
+
     $ for y in 2006 2007 2008 2009 2010; do echo; echo $y; hledger -f $y.ledger balance ^expenses --depth 2; done
 
+With `--flat`, a non-hierarchical list of full account names is displayed
+instead. This mode shows just the accounts actually contributing to the
+balance, making the arithmetic a little more obvious to non-hledger users.
+
 ##### chart
 
 The chart command saves a pie chart of your top account balances to an