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os/date

core-api



    cfunction
    src/core/os.c on line 1815, column 1

    (os/date &opt time local)

    Returns the given time as a date struct, or the current time if 
    `time` is not given. Returns a struct with following key values. 
    Note that all numbers are 0-indexed. Date is given in UTC unless 
    `local` is truthy, in which case the date is formatted for the 
    local timezone.

     $*$  :seconds  $-$  number of seconds [0-61]

     $*$  :minutes  $-$  number of minutes [0-59]

     $*$  :hours  $-$  number of hours [0-23]

     $*$  :month-day  $-$  day of month [0-30]

     $*$  :month  $-$  month of year [0, 11]

     $*$  :year  $-$  years since year 0 (e.g. 2019)

     $*$  :week-day  $-$  day of the week [0-6]

     $*$  :year-day  $-$  day of the year [0-365]

     $*$  :dst  $-$  if Day Light Savings is in effect

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# due to 0 indexing, you will often want to add 1 to things:
(defn short-date [d]
  (let [{:year y :month mon :month-day d} d]
    (string y "-" ( $+$  1 mon) "-" ( $+$  1 d))))

# Makes os/date like 2025-12-25
(short-date (os//date))


# From: https://codeberg.org/veqq/deforester/src/branch/master/deforester.janet
(defn time-string
  ``Gives current time as ISO 8601 string: 2025-10-12T11:43:14 https://en.wikipedia.org/wiki/ISO_8601
  This accounts for `os/date` 0-indexing month and days which are 1-indexed in ISO 8601.``
  []
  (let [{:year y :month mon :month-day d :hours h :minutes min :seconds s} (os/date)]
    (string y "-" ( $+$  1 mon) "-" ( $+$  1 d) "T" h ":" min ":" s)))

veqqqPlayground

(defn get-time-str []
  (let [{:hours h :minutes m :seconds s} (os/date)]
    (string h ":" m ":" s)))

(get-time-str) => "23:18:16"

tupini07Playground

(defn to-double-digit-string [digit]
  (string/slice (string "0" digit) -3))

(defn get-date-time-string [time]
  (let [date (os/date time)
        year (get date :year)
        month (to-double-digit-string (get date :month))
        day (to-double-digit-string (get date :month-day))
        hours (to-double-digit-string (get date :hours))
        minutes (to-double-digit-string (get date :minutes))
        seconds (to-double-digit-string (get date :seconds))]
    (string year "-" month "-" day "__" hours ":" minutes ":" seconds)))

(defn get-current-date-time-string []
  (get-date-time-string (os/time)))


### USAGE

(get-current-date-time-string)
# => "2020-09-23__17:20:00"

harryvederciPlayground

(os/date)
# => {:month 6 :dst false :year-day 185 :seconds 38 :minutes 44 :week-day 6 :year 2020 :hours 4 :month-day 3}

cellularmitosisPlayground

(def time (os/time))  # => 1593838001

(os/date t)
# => {:month 6 :dst false :year-day 185 :seconds 41 :minutes 46 :week-day 6 :year 2020 :hours 4 :month-day 3}
(os/date t false)
# => {:month 6 :dst false :year-day 185 :seconds 41 :minutes 46 :week-day 6 :year 2020 :hours 4 :month-day 3}

(os/date t true)
# => {:month 6 :dst true :year-day 184 :seconds 41 :minutes 46 :week-day 5 :year 2020 :hours 23 :month-day 2}
(os/date t :local)
# => {:month 6 :dst true :year-day 184 :seconds 41 :minutes 46 :week-day 5 :year 2020 :hours 23 :month-day 2}

cellularmitosisPlayground