imp: doc: Document new regular expression limited depth.

hledger/Hledger/Cli/CliOptions.hs

@@ -201,7 +201,7 @@ reportflags = [
  ,flagNone ["pending","P"]   (setboolopt "pending")  "include only pending postings/transactions"
  ,flagNone ["cleared","C"]   (setboolopt "cleared")  "include only cleared postings/transactions\n(-U/-P/-C can be combined)"
  ,flagNone ["real","R"]      (setboolopt "real")     "include only non-virtual postings"
- ,flagReq  ["depth"]         (\s opts -> Right $ setopt "depth" s opts) "NUM" "or -NUM: show only top NUM levels of accounts"
+ ,flagReq  ["depth"]         (\s opts -> Right $ setopt "depth" s opts) "DEPTHEXP" "if a number (or -NUM): show only top NUM levels of accounts. If REGEXP=NUM, only apply limiting to accounts matching the regular expression."
  ,flagNone ["empty","E"]     (setboolopt "empty") "Show zero items, which are normally hidden.\nIn hledger-ui & hledger-web, do the opposite."
 
   -- valuation

hledger/hledger.m4.md

@@ -5100,6 +5100,16 @@ reports will show accounts only to the specified depth, hiding deeper subaccount
 Use this when you want a summary with less detail.
 This flag has the same effect as a `depth:` query argument: `depth:2`, `--depth=2` or `-2` are equivalent.
 
+A regular expression can also be provided to limit the accounts to which the depth limit applies.
+This allows for different accounts to be limited to different levels, for example:
+`--depth assets=2`, `depth:assets=2` will both limit accounts matching `assets` to depth 2.
+If more than one regular expression matches, the most specific one will be used, i.e. the one which
+matches latest as you progress up the parents of the account.
+For example, `--depth savings=2 --depth assets=1` will clip to depth 2 when
+matching `assets:bank:savings`, as it matches only the full account name while `assets` also
+matches a parent.
+
+
 # Queries
 
 One of hledger's strengths is being able to quickly report on a precise subset of your data.