On May 21, 2013, at 10:05 PM, Lewis wrote: > Thanks! I didn't know you could construct dates like that. > > According to the docs, the #f argument should give UTC. Unfortunately > on my machine it gives > > (date* 0 0 12 22 5 2013 3 141 #f 43200 0 "NZST") > > Which is local time for me. Perhaps this is a bug?
Doesn't look that way to me; I read it as 12:00 noon on May 22nd in your time zone, which I believe is the same moment as 0:00 midnight UTC. However, it also appears that by passing a #f to the seconds->date function, you can in fact have a UTC date if you prefer it: #lang racket (require racket/date) (seconds->date (find-seconds 0 0 0 22 05 2013 #f) #f) Best, John Clements > > On 22/05/2013, John Clements <cleme...@brinckerhoff.org> wrote: >> >> On May 21, 2013, at 8:51 PM, Lewis wrote: >> >>> When I use string->date in srfi/19, it defaults to my local time zone. >>> I see from the documentation that one can use "~z" to denote the "time >>> zone in RFC-822 style". A quick google of RFC-822 suggests "UT" is the >>> correct abbreviation for UTC. >>> >>> However >>> >>> Welcome to Racket v5.3.4. >>>> (require srfi/19) >>>> (string->date "22/05/13/UT" "~d/~m/~y/~z") >>> string->date: TIME-ERROR type bad-date-format-string: "~d/~m/~y/~z" >>> context...: >>> /usr/lib/racket/collects/srfi/19/time.rkt:1532:0: tm:string->date >>> /usr/lib/racket/collects/srfi/19/time.rkt:1569:0: string->date >>> /usr/lib/racket/collects/racket/private/misc.rkt:87:7 >>> >>> So in short: how - given the day, month and year - can I construct a >>> date object that's in UTC? >> >> How important is it to you to use srfi/19? >> >> The program below produces the date that you're looking for, if I understand >> correctly: >> >> >> #lang racket >> >> (require racket/date) >> >> (seconds->date (find-seconds 0 0 0 22 05 2013 #f)) >> >> >> ____________________ Racket Users list: http://lists.racket-lang.org/users
