as https://golang.org/pkg/time/#Date says:
The month, day, hour, min, sec, and nsec values may be outside their usual ranges and will be normalized during the conversion. For example, October 32 converts to November 1. On Tue, Oct 23, 2018 at 3:12 PM <alan.f...@gmail.com> wrote: > > If you check the source code for the time.Date() function, you'll find that > it does indeed normalize the date by calling a private 'norm' function. > > So, if you enter a month of 13, it will overflow into January of the > following year. > > My guess is that they thought this was a better solution than returning an > error. It's also a convenient way to adjust a date (forwards or backwards) at > the same time as you initialize it. > > Alan > > On Tuesday, October 23, 2018 at 9:20:29 PM UTC+1, Taras D wrote: >> >> Yes sorry -1 is a valid year. >> >> An invalid month is any integer outside of [1,12]. We can always define >> month 13 as January if we adopt Z_12, but I expected an error to occur. >> Accepting months outside of [1,12] violates the Principle of least >> astonishment. >> >> For comparison, python verifies the month integer: >> >> ----> 1 datetime.date(2000, 13, 1) >> ValueError: month must be in 1..12 >> >> >> So does golang accept these values because: >> - a sensible definition exists for values outside of [1,12]? >> - for performance reasons? >> >> Taras >> >> On Wednesday, 24 October 2018 01:23:35 UTC+11, Volker Dobler wrote: >>> >>> Why is year -1 invalid and what is an "invalid" month >>> given that 13==1 in Z_12? >>> >>> V. >>> >>> >>> >>> On Tuesday, 23 October 2018 16:01:00 UTC+2, Taras D wrote: >>>> >>>> Hi, >>>> >>>> I was surprised to find the following worked without any reported errors: >>>> >>>> t1 := time.Date(-1, 1, 10, 23, 0, 0, 0, time.UTC) // invalid year >>>> t2 := time.Date(2000, 13, 10, 23, 0, 0, 0, time.UTC) // invalid month >>>> m := time.Month(13) // invalid month >>>> >>>> What is the rationale in accepting invalid month/year values? > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
