@@ -6,9 +6,26 @@
66-- Maintainer: Leon P Smith <leon@melding-monads.com>
77-- Stability: experimental
88--
9−-- Time types that supports infinities. Also includes new time parsers
10−-- with improved performance over GHC's time package. See
11−-- 'Database.PostgreSQL.Simple.Time.Internal'.
9+-- Time types that supports positive and negative infinity. Also includes
10+-- new time parsers and printers with better performance than GHC's time package.
11+-- The parsers only understand the specific variant of ISO 8601 that PostgreSQL
12+-- emits, and the printers attempt to duplicate this syntax. These likely have
13+-- problems and shortcomings. Some that I know of:
14+--
15+-- 1. Timestamps with time zones before @1883-Nov-18 12:00:00-05@, the moment
16+-- Standard Railway Time went live, cannot be parsed. This is because
17+-- PostgreSQL will emit @1883-11-18 12:03:57-04:56:02@ instead of
18+-- @1883-11-18 11:59:59-05@, and the timezone parser is incomplete.
19+-- Timestamps without time zones do not have this problem.
20+--
21+-- 2. Dates an times surrounding @1582-Feb-24@, the date the Gregorian
22+-- Calendar was introduced, should be investigated for conversion errors.
23+--
24+-- 3. Points in time Before Christ are not also not supported. For example,
25+-- PostgreSQL will emit @0045-01-01 BC@ for a value of a @date@ type.
26+-- This is the year that the Julian Calendar was adopted.
27+--
28+-- However, it should be noted that the old parsers also had these issues.
1229--
1330------------------------------------------------------------------------------
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