From 289d219758336e1e1d8afe36255fe06079d8daeb Mon Sep 17 00:00:00 2001 From: Nobuyoshi Nakada Date: Mon, 8 Aug 2022 21:13:52 +0900 Subject: [ruby/date] [DOC] Fix about calendars difference https://github.com/ruby/date/commit/0ae93e26aa --- doc/date/calendars.rdoc | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/doc/date/calendars.rdoc b/doc/date/calendars.rdoc index e2118d3e9d..b8690841b1 100644 --- a/doc/date/calendars.rdoc +++ b/doc/date/calendars.rdoc @@ -4,19 +4,16 @@ The difference between the {Julian calendar}[https://en.wikipedia.org/wiki/Julian_calendar] and the {Gregorian calendar}[https://en.wikipedia.org/wiki/Gregorian_calendar] -may matter to your program if it uses dates in the interval: +may matter to your program if it uses dates before the switchovers. - October 15, 1582. - September 14, 1752. -A date outside that interval (including all dates in modern times) -is the same in both calendars. -However, a date _within_ that interval will be different -in the two calendars. +A date will be different in the two calendars, in general. -=== Different Calendar, Different \Date +=== Different switchover dates -The reason for the difference is this: +The reasons for the difference are religious/political histories. - On October 15, 1582, several countries changed from the Julian calendar to the Gregorian calendar; @@ -25,10 +22,12 @@ The reason for the difference is this: - On September 14, 1752, most of the British empire changed from the Julian calendar to the Gregorian calendar. -When your code uses a date in this "gap" interval, +When your code uses a date before these switchover dates, it will matter whether it considers the switchover date to be the earlier date or the later date (or neither). +See also {a concrete example here}[rdoc-ref:DateTime@When+should+you+use+DateTime+and+when+should+you+use+Time-3F]. + === Argument +start+ Certain methods in class \Date handle differences in the -- cgit v1.2.3