imp: add "since" as a synonym of "from" in period expressions (ledger compat)

hledger-lib/Hledger/Data/Dates.hs

@@ -904,6 +904,8 @@ weekdaysp = fmap head . group . sort <$> sepBy1 weekday (string' ",")
 -- Right (DayOfYear 11 29,DateSpan 2009-01-01..)
 -- >>> p "every 11/29 from 2009"
 -- Right (DayOfYear 11 29,DateSpan 2009-01-01..)
+-- >>> p "every 11/29 since 2009"
+-- Right (DayOfYear 11 29,DateSpan 2009-01-01..)
 -- >>> p "every 2nd Thursday of month to 2009"
 -- Right (WeekdayOfMonth 2 4,DateSpan ..2008-12-31)
 -- >>> p "every 1st monday of month to 2009"
@@ -1004,7 +1006,7 @@ periodexprdatespanp rdate = choice $ map try [
 -- Right DateSpan 2017
 doubledatespanp :: Day -> TextParser m DateSpan
 doubledatespanp rdate = liftA2 fromToSpan
-    (optional (string' "from" *> skipNonNewlineSpaces) *> smartdate)
+    (optional ((string' "from" <|> string' "since") *> skipNonNewlineSpaces) *> smartdate)
     (skipNonNewlineSpaces *> choice [string' "to", string "..", string "-"]
     *> skipNonNewlineSpaces *> smartdate)
   where
@@ -1027,7 +1029,7 @@ quarterdatespanp rdate = do
 
 fromdatespanp :: Day -> TextParser m DateSpan
 fromdatespanp rdate = fromSpan <$> choice
-    [ string' "from" *> skipNonNewlineSpaces *> smartdate
+    [ (string' "from" <|> string' "since") *> skipNonNewlineSpaces *> smartdate
     , smartdate <* choice [string "..", string "-"]
     ]
   where

hledger/hledger.m4.md

@@ -4362,7 +4362,7 @@ earliest or latest transaction in your journal:
 |                      |                                   |
 |----------------------|-----------------------------------|
 | `-p "from 2009/1/1"` | everything after january 1, 2009  |
-| `-p "from 2009/1"`   | the same                          |
+| `-p "since 2009/1"`  | the same, since is a synonym      |
 | `-p "from 2009"`     | the same                          |
 | `-p "to 2009"`       | everything before january 1, 2009 |