lambdaisland.deja-fu — com.lambdaisland/deja-fu 1.6.65

Time/Date types for use on the frontend. This provides the following equivalents:

| #time/date "2020-10-10" | java.time.LocalDate | goog.date.Date | | #time/time "05:30:45" | java.time.LocalTime | lambdaisland.deja-fu/LocalTime | | #time/date-time "2020-10-07T12:16:41.761088" | java.time.LocalDateTime | goog.date.DateTime |

For all of these we make sure the tagged reader literals are read correctly, and that values of these types print with these reader tags.

All times are "local", they don't carry timezone information.

We also implement an ad-hoc API here, adding things as we need them, making sure that these functions hide the details of these types. All date/time manipulation on the frontend should go through this namespace. Avoid calling properties/methods of concrete types directly, and avoid using js/Date.

Create a new local-date-time using the same syntax from goog.Date or js/Date: (local-date-time 2021 4 19 15 39 0 0)

Parse a time string: (parse-local-date-time "2021-01-01T23:59")

Get the current time: (local-date-time)

Adjust the seconds component: (assoc (local-date-time) :seconds 0)

Get the next day: (add-interval (local-date-time) {:hours 1})

Works well with threading: (-> (parse-local-date-time "2021-01-01T23:59") (assoc :seconds 0) (to-local-date))

browser-timezone-offset cljs

(browser-timezone-offset)

Get the difference, in minutes, between browser's time zone and UTC. e.g. when in CET (+1) this returns -60.

Conversions cljs protocol

add-interval cljs

(add-interval obj values)

Add an interval to the date/time

epoch-ms cljs

(epoch-ms obj)

Milliseconds since January 1, 1970

to-local-date cljs

(to-local-date obj)

Date part of a date or date-time

to-local-time cljs

(to-local-time obj)

Time part of a date-time or local time

with-date cljs

(with-date obj date)

Set the date part of a DateTime

with-time cljs

(with-time obj time)

Set the time part of a DateTime

current-time-millis cljs

(current-time-millis)

Get the current UNIX timestamp in milliseconds.

date-string-regex cljs

days-between cljs

(days-between begin end)

Get the interval between two date/time objects in days

distance-in-words cljs

(distance-in-words from to)

(distance-in-words from
                   to
                   {:keys [patterns] :or {patterns relative-time-patterns}})

Format cljs protocol

format cljs

(format obj)

(format obj format-str)

Symbol Meaning Presentation Example

---

G# era designator (Text) AD y# year (Number) 1996 Y year (week of year) (Number) 1997 u* extended year (Number) 4601 Q# quarter (Text) Q3 & 3rd quarter M month in year (Text & Number) July & 07 L month in year (standalone) (Text & Number) July & 07 d day in month (Number) 10 h hour in am/pm (1~12) (Number) 12 H hour in day (0~23) (Number) 0 m minute in hour (Number) 30 s second in minute (Number) 55 S fractional second (Number) 978 E# day of week (Text) Tue & Tuesday e* day of week (local 1~7) (Number) 2 c# day of week (standalone) (Text & Number) 2 & Tues & Tuesday & T D* day in year (Number) 189 F* day of week in month (Number) 2 (2nd Wed in July) w week in year (Number) 27 W* week in month (Number) 2 a am/pm marker (Text) PM k hour in day (1~24) (Number) 24 K hour in am/pm (0~11) (Number) 0 z time zone (Text) Pacific Standard Time Z# time zone (RFC 822) (Number) -0800 v# time zone (generic) (Text) America/Los_Angeles V# time zone (Text) Los Angeles Time g* Julian day (Number) 2451334 A* milliseconds in day (Number) 69540000 ' escape for text (Delimiter) 'Date=' '' single quote (Literal) 'o''clock'

Item marked with '*' are not supported yet. Item marked with '#' works different than java

The count of pattern letters determine the format.

• (Text) 4 or more, use full form, <4, use short or abbreviated form if it exists. (e.g., "EEEE" produces "Monday", "EEE" produces "Mon")

• (Number) the minimum number of digits. Shorter numbers are zero-padded to this amount (e.g. if "m" produces "6", "mm" produces "06"). Year is handled specially; that is, if the count of 'y' is 2, the Year will be truncated to 2 digits. (e.g., if "yyyy" produces "1997", "yy" produces "97".) Unlike other fields, fractional seconds are padded on the right with zero.

• (Text & Number) 3 or over, use text, otherwise use number. (e.g., "M" produces "1", "MM" produces "01", "MMM" produces "Jan", and "MMMM" produces "January".)

Any characters in the pattern that are not in the ranges of ['a'..'z'] and ['A'..'Z'] will be treated as quoted text. For instance, characters like ':', '.', ' ', '#' and '@' will appear in the resulting time text even if they are not inside single quotes.

formatter cljs

leap-year? cljs

(leap-year? year-or-date-like)

Does the year, or the year field of the given local date/date-time, a leap year?

local-date cljs

(local-date)

(local-date year month day)

contstructs a goog.date.Date

• no arguments: returns the date for today
• multiple arguments: takes year,month,day

local-date-time cljs

(local-date-time)

(local-date-time epoch-ms)

(local-date-time year month day hours minutes)

(local-date-time year month day hours minutes seconds)

(local-date-time year month day hours minutes seconds nanos)

contstructs a goog.date.DateTime

• no arguments: get the current date and time
• single argument: convert UNIX timestamp (milliseconds) to a DateTime
• multiple arguments: takes year,month,day,hours,minutes,seconds,nanos. Seconds and nanos are optional.

local-time cljs

(local-time)

(local-time hours & args)

constructs a LocalTime

• no arguments: get the current time
• multiple arguments: takes hours,minutes,seconds,nanos

millis-between cljs

(millis-between begin end)

Get the interval between two date/time objects in milliseconds

minutes-between cljs

(minutes-between begin end)

Get the interval between two date/time objects in minutes

parse-local-date cljs

(parse-local-date yyyy-mm-dd)

Parse a date (YYYY-MM-DD) to a goog.date.Date

Reimplementation of goog.date.Date.fromIsostring but with support for single digit month/day.

parse-local-date-time cljs

(parse-local-date-time date-time)

Parse an ISO timestamp without time zone information to a goog.date.DateTime. We implement our own parsing logic for the time section, to prevent time zone shifting. The numbers you provide in the timestamp are the numbers that end up in the DateTime. If we leave it to goog.date then it will assume the timestamp is UTC, and shift it to the browser's timezone.

parse-local-time cljs

(parse-local-time time)

Parse a timestamp (HH:MM:SS or HH:MM:SS.mmm or HH:MM:SS.nnnnnn) to a LocalTime.

parse-offset-date-time cljs

(parse-offset-date-time date-time)

Parse an ISO timestamp with timezone offset (Z or +/-) to a goog.date.DateTime. Note that the result is essentially a LocalDateTime, since none of the types at our disposal on the frontend actually store a timezone or offset. Instead goog.date's parsing logic will shift the time based on the difference between the time zone in the timestamp, and the timezone the browser is in.

relative-time-patterns cljs

Word patterns, can be passed in for i18n

today cljs

(today)

Get a #time/date with the current date, convenience API alternative to calling (local-date) without args.

utc-now cljs

(utc-now)

Get a local-date-time, representing the current time in UTC.