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Date & Time ​

Current Time ​

time/now ​

Return the current time as a Unix timestamp in seconds (with fractional milliseconds).

scheme
(time/now)   ; => 1707955200.123

time-ms ​

Return the current time as Unix milliseconds (integer).

scheme
(time-ms)   ; => 1707955200123

Formatting & Parsing ​

time/format ​

Format a Unix timestamp using a format string. Uses strftime-style directives.

scheme
(time/format (time/now) "%Y-%m-%d")        ; => "2025-02-15"
(time/format (time/now) "%H:%M:%S")        ; => "14:30:00"
(time/format (time/now) "%Y-%m-%d %H:%M")  ; => "2025-02-15 14:30"

time/parse ​

Parse a date string into a Unix timestamp using a format string.

scheme
(time/parse "2025-01-15" "%Y-%m-%d")        ; => 1736899200.0
(time/parse "2025-01-15 10:30" "%Y-%m-%d %H:%M")

Date Decomposition ​

time/date-parts ​

Decompose a Unix timestamp into a map of date/time components.

scheme
(time/date-parts (time/now))
; => {:year 2025 :month 2 :day 15 :hour 14 :minute 30 :second 0 ...}

Arithmetic ​

time/add ​

Add seconds to a timestamp.

scheme
(time/add (time/now) 86400)     ; one day later
(time/add (time/now) 3600)      ; one hour later
(time/add (time/now) -86400)    ; one day earlier

time/diff ​

Compute the difference between two timestamps in seconds.

scheme
(define t1 (time/now))
;; ... some work ...
(define t2 (time/now))
(time/diff t1 t2)   ; => elapsed seconds

Delay ​

sleep ​

Sleep for a given number of milliseconds.

scheme
(sleep 1000)   ; sleep for 1 second
(sleep 500)    ; sleep for 500ms