PeriodData's use of Int keys caused wrong results with periodic
reports involving dates outside the machine-specific limits of Int.
Those were:
64 bits: -25252734927764696-04-22..25252734927768413-06-12
32 bits: -5877752-05-08..5881469-05-27
16 bits: 1769-02-28..1948-08-04
8 bits: 1858-07-12..1859-03-24
32 bits is supported by MicroHS; 16 and 8 bits aren't supported by
any known haskell version, but that could change in future.
For example, on 64 bit machines we got:
25252734927768413-06-12 PeriodData's max date
(expenses) 1
25252734927768414-01-01 next year past PeriodData's max date
(expenses) 2
$ hledger reg -O csv --yearly
"txnidx","date","code","description","account","amount","total"
"0","-25252734927764696-11-10","","","expenses","1","1"
Now it uses Integer (like the time package), fixing the bug.
And benchmarking shows memory and time usage slightly improved
(surprisingly; tested with up to 500 subperiods, eg
hledger -f examples/10ktxns-1kaccts.journal reg -1 cur:A -D >/dev/null)
438c4a0469