Date

Functions for interacting with JavaScript Dates.

compare

RES

let compare: (t, t) => Ordering.t

compare(date1, date2) compares two dates chronologically, returns an Ordering.t value.

Examples

RES
Date.compare(Date.fromString("2023-01-01"), Date.fromString("2023-01-01")) == Ordering.equal
Date.compare(Date.fromString("2023-01-01"), Date.fromString("2023-01-02")) == Ordering.less
Date.compare(Date.fromString("2023-01-02"), Date.fromString("2023-01-01")) == Ordering.greater

equal

RES

let equal: (t, t) => bool

equal(date1, date2) checks if two dates represent the same point in time.

Examples

RES
Date.equal(Date.fromString("2023-01-01"), Date.fromString("2023-01-01")) == true
Date.equal(Date.fromString("2023-01-01"), Date.fromString("2023-01-02")) == false

fromString

RES

let fromString: string => t

fromString(dateTimeString)

Creates a date object from given date time string. The string has to be in the ISO 8601 format YYYY-MM-DDTHH:mm:ss.sssZ (https://tc39.es/ecma262/#sec-date-time-string-format).

Invalid date time strings will create invalid dates. You can use the result like any valid date, but many functions like toString will return "Invalid Date" or functions like Date.getTime will return NaN.

Examples

RES
Date.fromString("2023") // 2023-01-01T00:00:00.000Z

Date.fromString("2023-02-20") // 2023-02-20T00:00:00.000Z

Date.fromString("2023-02-20T16:40:00.00Z") // 2023-02-20T16:40:00.000Z

Date.fromString("") // Invalid Date

Date.fromString("")->Date.getTime // NaN

fromTime

RES

let fromTime: msSinceEpoch => t

fromTime(msSinceEpoch)

Creates a date object from the given time in milliseconds since / until UNIX epoch (January 1, 1970 00:00:00 UTC). Positive numbers create dates after epoch, negative numbers create dates before epoch.

Examples

RES
Date.fromTime(0.0)
// 1970-01-01T00:00:00.000Z

Date.fromTime(-86_400_000.0)
// 1969-12-31T00:00:00.000Z

Date.fromTime(86_400_000.0)
// 1970-01-02T00:00:00.000Z

getDate

RES

let getDate: t => int

getDate(date)

Returns the date (day of month) of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getDate
// 20

getDay

RES

let getDay: t => int

getDay(date)

Returns the day of week of a given date (according to local time). 0 = Sunday, 1 = Monday, ... 6 = Saturday

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getDay
// 1

getFullYear

RES

let getFullYear: t => int

getFullYear(date)

Returns the year of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20")->Date.getFullYear
// 2023

getHours

RES

let getHours: t => int

getHours(date)

Returns the hours of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getHours
// 16

getMilliseconds

RES

let getMilliseconds: t => int

getMilliseconds(date)

Returns the milliseconds of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getMilliseconds
// 0

getMinutes

RES

let getMinutes: t => int

getMinutes(date)

Returns the minutes of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getMinutes
// 40

getMonth

RES

let getMonth: t => int

getMonth(date)

Returns the month (0-indexed) of a given date (according to local time).

Examples

RES
Date.fromString("2023-01-01")->Date.getMonth
// 0

getSeconds

RES

let getSeconds: t => int

getSeconds(date)

Returns the seconds of a given date (according to local time).

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.getSeconds
// 0

getTime

RES

let getTime: t => msSinceEpoch

getTime(date)

Returns the time, in milliseconds, between UNIX epoch (January 1, 1970 00:00:00 UTC) and the current date time. Invalid dates will return NaN. Dates before epoch will return negative numbers.

Examples

RES
Date.fromString("2023-02-20")->Date.getTime
// 1676851200000

getTimezoneOffset

RES

let getTimezoneOffset: t => int

getTimezoneOffset(date)

Returns the time in minutes between the UTC time and the locale time. The timezone of the given date doesn't matter.

Examples

RES
Date.fromString("2023-01-01")->Date.getTimezoneOffset
// -60 with local time zone = Europe/Berlin

Date.fromString("2023-06-01")->Date.getTimezoneOffset
// -120 with local time zone = Europe/Berlin

getUTCDate

RES

let getUTCDate: t => int

getUTCDate(date)

Returns the date (day of month) of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCDate // 31

getUTCDay

RES

let getUTCDay: t => int

getUTCDay(date)

Returns the day (day of week) of a given date (according to UTC time). 0 = Sunday, 1 = Monday, ... 6 = Saturday

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCDay // 6

getUTCFullYear

RES

let getUTCFullYear: t => int

getUTCFullYear(date)

Returns the year of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCFullYear // 2022

getUTCHours

RES

let getUTCHours: t => int

getUTCHours(date)

Returns the hours of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCHours // 23

getUTCMilliseconds

RES

let getUTCMilliseconds: t => int

getUTCMilliseconds(date)

Returns the milliseconds of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCMilliseconds // 0

getUTCMinutes

RES

let getUTCMinutes: t => int

getUTCMinutes(date)

Returns the minutes of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCMinutes // 0

getUTCMonth

RES

let getUTCMonth: t => int

getUTCMonth(date)

Returns the month of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCMonth // 11

getUTCSeconds

RES

let getUTCSeconds: t => int

getUTCSeconds(date)

Returns the seconds of a given date (according to UTC time).

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.getUTCSeconds // 0

ignore

RES

let ignore: t => unit

ignore(date) ignores the provided date and returns unit.

This helper is useful when you want to discard a value (for example, the result of an operation with side effects) without having to store or process it further.

localeOptions

RES

type localeOptions = {
  dateStyle?: [#full | #long | #medium | #short],
  timeStyle?: [#full | #long | #medium | #short],
  weekday?: [#long | #narrow | #short],
  era?: [#long | #narrow | #short],
  year?: [#"2-digit" | #numeric],
  month?: [
    | #"2-digit"
    | #long
    | #narrow
    | #numeric
    | #short
  ],
  day?: [#"2-digit" | #numeric],
  hour?: [#"2-digit" | #numeric],
  minute?: [#"2-digit" | #numeric],
  second?: [#"2-digit" | #numeric],
  timeZoneName?: [#long | #short],
}

A type representing date time format options.

Note: There are some properties missing:

fractionalSecondDigits
dayPeriod
calendar
numberingSystem
localeMatcher
timeZone
hour12
hourCycle
formatMatcher

See full spec at https://tc39.es/ecma402/#datetimeformat-objects

make

RES

let make: unit => t

make()

Creates a date object with the current date time as value.

Examples

RES
Date.make()

makeWithYM

RES

let makeWithYM: (~year: int, ~month: int) => t

Creates a date object with the given year and month. Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYM(~year=2023, ~month=0)
// 2023-01-01T00:00:00.000Z

Date.makeWithYM(~year=2023, ~month=11)
// 2023-12-01T00:00:00.000Z

Date.makeWithYM(~year=2023, ~month=12)
// 2024-01-01T00:00:00.000Z

Date.makeWithYM(~year=2023, ~month=-1)
// 2022-12-01T00:00:00.000Z

// Note: The output depends on your local time zone.
// In nodejs you can change it by using the TZ env (`export TZ='Europe/London' && node index.bs.js`)

makeWithYMD

RES

let makeWithYMD: (~year: int, ~month: int, ~day: int) => t

Creates a date object with the given year, month and date (day of month). Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYMD(~year=2023, ~month=1, ~day=20)
// 2023-02-20T00:00:00.000Z

Date.makeWithYMD(~year=2023, ~month=1, ~day=-1)
// 2022-11-29T00:00:00.000Z

Date.makeWithYMD(~year=2023, ~month=1, ~day=29)
// 2023-03-01T00:00:00.000Z

makeWithYMDH

RES

let makeWithYMDH: (~year: int, ~month: int, ~day: int, ~hours: int) => t

Creates a date object with the given year, month, date (day of month) and hours. Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYMDH(~year=2023, ~month=1, ~day=20, ~hours=16)
// 2023-02-20T16:00:00.000Z

Date.makeWithYMDH(~year=2023, ~month=1, ~day=20, ~hours=24)
// 2023-02-21T00:00:00.000Z

Date.makeWithYMDH(~year=2023, ~month=1, ~day=20, ~hours=-1)
// 2023-02-19T23:00:00.000Z

// Note: The output depends on your local time zone.
// In nodejs you can change it by using the TZ env (`export TZ='Europe/London' && node index.bs.js`)

makeWithYMDHM

RES

let makeWithYMDHM: (
  ~year: int,
  ~month: int,
  ~day: int,
  ~hours: int,
  ~minutes: int,
) => t

Creates a date object with the given year, month, date (day of month), hours and minutes. Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYMDHM(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=40)
// 2023-02-20T16:40:00.000Z

Date.makeWithYMDHM(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=60)
// 2023-02-20T17:00:00.000Z

Date.makeWithYMDHM(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=-1)
// 2023-02-20T15:59:00.000Z

// Note: The output depends on your local time zone.
// In nodejs you can change it by using the TZ env (`export TZ='Europe/London' && node index.bs.js`)

makeWithYMDHMS

RES

let makeWithYMDHMS: (
  ~year: int,
  ~month: int,
  ~day: int,
  ~hours: int,
  ~minutes: int,
  ~seconds: int,
) => t

Creates a date object with the given year, month, date (day of month), hours, minutes and seconds. Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYMDHMS(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=40, ~seconds=0)
// 2023-02-20T16:40:00.000Z

Date.makeWithYMDHMS(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=40, ~seconds=60)
// 2023-02-20T16:41:00.000Z

Date.makeWithYMDHMS(~year=2023, ~month=1, ~day=20, ~hours=16, ~minutes=40, ~seconds=-1)
// 2023-02-20T16:39:59.000Z

// Note: The output depends on your local time zone.
// In nodejs you can change it by using the TZ env (`export TZ='Europe/London' && node index.bs.js`)

makeWithYMDHMSM

RES

let makeWithYMDHMSM: (
  ~year: int,
  ~month: int,
  ~day: int,
  ~hours: int,
  ~minutes: int,
  ~seconds: int,
  ~milliseconds: int,
) => t

Creates a date object with the given year, month, date (day of month), hours, minutes, seconds and milliseconds. Be aware of using a value for year < 100, because it behaves inconsistent (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#interpretation_of_two-digit_years). Months are 0-indexed (0 = January, 11 = December). Values, which are out of range, will be carried over to the next bigger unit (s. example).

Examples

RES
Date.makeWithYMDHMSM(
  ~year=2023,
  ~month=1,
  ~day=20,
  ~hours=16,
  ~minutes=40,
  ~seconds=0,
  ~milliseconds=0,
)
// 2023-02-20T16:40:00.000Z

Date.makeWithYMDHMSM(
  ~year=2023,
  ~month=1,
  ~day=20,
  ~hours=16,
  ~minutes=40,
  ~seconds=0,
  ~milliseconds=1000,
)
// 2023-02-20T16:40:01.000Z

Date.makeWithYMDHMSM(
  ~year=2023,
  ~month=1,
  ~day=20,
  ~hours=16,
  ~minutes=40,
  ~seconds=0,
  ~milliseconds=-1,
)
// 2023-02-20T16:39:59.999Z

// Note: The output depends on your local time zone.
// In nodejs you can change it by using the TZ env (`export TZ='Europe/London' && node index.bs.js`)

msSinceEpoch

RES

type msSinceEpoch = float

Time, in milliseconds, since / until the UNIX epoch (January 1, 1970 00:00:00 UTC). Positive numbers represent dates after, negative numbers dates before epoch.

now

RES

let now: unit => msSinceEpoch

now()

Returns the time, in milliseconds, between UNIX epoch (January 1, 1970 00:00:00 UTC) and the current date time.

setDate

RES

let setDate: (t, int) => unit

setDate(date, day)

Sets the date (day of month) of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setDate(1)

setFullYear

RES

let setFullYear: (t, int) => unit

setFullYear(date, year)

Sets the year of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setFullYear(2024)

setFullYearM

RES

let setFullYearM: (t, ~year: int, ~month: int) => unit

setFullYearM(date, ~year, ~month)

Sets the year and month of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setFullYearM(~year=2024, ~month=0)

setFullYearMD

RES

let setFullYearMD: (t, ~year: int, ~month: int, ~day: int) => unit

setFullYearMD(date, ~year, ~month, ~day)

Sets the year, month and date (day of month) of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setFullYearMD(~year=2024, ~month=0, ~day=1)

setHours

RES

let setHours: (t, int) => unit

setHours(date, hours)

Sets the hours of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setHours(0)

setHoursM

RES

let setHoursM: (t, ~hours: int, ~minutes: int) => unit

setHoursM(date, ~hours, ~minutes)

Sets the hours and minutes of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setHoursM(~hours=0, ~minutes=0)

setHoursMS

RES

let setHoursMS: (t, ~hours: int, ~minutes: int, ~seconds: int) => unit

setHoursMS(date, ~hours, ~minutes, ~seconds)

Sets the hours, minutes and seconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setHoursMS(~hours=0, ~minutes=0, ~seconds=0)

setHoursMSMs

RES

let setHoursMSMs: (
  t,
  ~hours: int,
  ~minutes: int,
  ~seconds: int,
  ~milliseconds: int,
) => unit

setHoursMSMs(date, ~hours, ~minutes, ~seconds, ~milliseconds)

Sets the hours, minutes, seconds and milliseconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setHoursMSMs(
  ~hours=0,
  ~minutes=0,
  ~seconds=0,
  ~milliseconds=0,
)

setMilliseconds

RES

let setMilliseconds: (t, int) => unit

setMilliseconds(date, milliseconds)

Sets the milliseconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setMilliseconds(0)

setMinutes

RES

let setMinutes: (t, int) => unit

setMinutes(date, minutes)

Sets the minutes of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setMinutes(0)

setMinutesS

RES

let setMinutesS: (t, ~minutes: int, ~seconds: int) => unit

setMinutesS(date, ~minutes, ~seconds)

Sets the minutes and seconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setMinutesS(~minutes=0, ~seconds=0)

setMinutesSMs

RES

let setMinutesSMs: (
  t,
  ~minutes: int,
  ~seconds: int,
  ~milliseconds: int,
) => unit

setMinutesSMs(date, ~minutes, ~seconds, ~milliseconds)

Sets the minutes, seconds and milliseconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setMinutesSMs(
  ~minutes=0,
  ~seconds=0,
  ~milliseconds=0,
)

setMonth

RES

let setMonth: (t, int) => unit

setMonth(date, month)

Sets the month of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setMonth(0)

setSeconds

RES

let setSeconds: (t, int) => unit

setSeconds(date, seconds)

Sets the seconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setSeconds(0)

setSecondsMs

RES

let setSecondsMs: (t, ~seconds: int, ~milliseconds: int) => unit

setSecondsMs(date, ~seconds, ~milliseconds)

Sets the seconds and milliseconds of a date (according to local time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setSecondsMs(~seconds=0, ~milliseconds=0)

setUTCDate

RES

let setUTCDate: (t, int) => unit

setDate(date, day)

Sets the date (day of month) of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCDate(1)

setUTCFullYear

RES

let setUTCFullYear: (t, int) => unit

setUTCFullYear(date, year)

Sets the year of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCFullYear(2024)

setUTCFullYearM

RES

let setUTCFullYearM: (t, ~year: int, ~month: int) => unit

setUTCFullYearM(date, ~year, ~month)

Sets the year and month of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCFullYearM(~year=2024, ~month=0)

setUTCFullYearMD

RES

let setUTCFullYearMD: (t, ~year: int, ~month: int, ~day: int) => unit

setUTCFullYearMD(date, ~year, ~month, ~day)

Sets the year, month and date (day of month) of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCFullYearMD(~year=2024, ~month=0, ~day=1)

setUTCHours

RES

let setUTCHours: (t, int) => unit

setUTCHours(date, hours)

Sets the hours of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCHours(0)

setUTCHoursM

RES

let setUTCHoursM: (t, ~hours: int, ~minutes: int) => unit

setHoursM(date, ~hours, ~minutes)

Sets the hours and minutes of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCHoursM(~hours=0, ~minutes=0)

setUTCHoursMS

RES

let setUTCHoursMS: (t, ~hours: int, ~minutes: int, ~seconds: int) => unit

setUTCHoursMS(date, ~hours, ~minutes, ~seconds)

Sets the hours, minutes and seconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCHoursMS(~hours=0, ~minutes=0, ~seconds=0)

setUTCHoursMSMs

RES

let setUTCHoursMSMs: (
  t,
  ~hours: int,
  ~minutes: int,
  ~seconds: int,
  ~milliseconds: int,
) => unit

setUTCHoursMSMs(date, ~hours, ~minutes, ~seconds, ~milliseconds)

Sets the hours, minutes, seconds and milliseconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCHoursMSMs(
  ~hours=0,
  ~minutes=0,
  ~seconds=0,
  ~milliseconds=0,
)

setUTCMilliseconds

RES

let setUTCMilliseconds: (t, int) => unit

setUTCMilliseconds(date, milliseconds)

Sets the milliseconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCMilliseconds(0)

setUTCMinutes

RES

let setUTCMinutes: (t, int) => unit

setUTCMinutes(date, minutes)

Sets the minutes of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCMinutes(0)

setUTCMinutesS

RES

let setUTCMinutesS: (t, ~minutes: int, ~seconds: int) => unit

setUTCMinutesS(date, ~minutes, ~seconds)

Sets the minutes and seconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCMinutesS(~minutes=0, ~seconds=0)

setUTCMinutesSMs

RES

let setUTCMinutesSMs: (
  t,
  ~minutes: int,
  ~seconds: int,
  ~milliseconds: int,
) => unit

setUTCMinutesSMs(date, ~minutes, ~seconds, ~milliseconds)

Sets the minutes, seconds and milliseconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCMinutesSMs(
  ~minutes=0,
  ~seconds=0,
  ~milliseconds=0,
)

setUTCMonth

RES

let setUTCMonth: (t, int) => unit

setUTCMonth(date, month)

Sets the month of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCMonth(0)

setUTCSeconds

RES

let setUTCSeconds: (t, int) => unit

setUTCSeconds(date, seconds)

Sets the seconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCSeconds(0)

setUTCSecondsMs

RES

let setUTCSecondsMs: (t, ~seconds: int, ~milliseconds: int) => unit

setUTCSecondsMs(date, ~seconds, ~milliseconds)

Sets the seconds and milliseconds of a date (according to UTC time). Beware this will mutate the date.

Examples

RES
Date.fromString("2023-02-20T16:40:00.00")->Date.setUTCSecondsMs(~seconds=0, ~milliseconds=0)

t

RES

type t

A type representing a JavaScript date.

toDateString

RES

let toDateString: t => string

toDateString(date)

Converts a JavaScript date to a standard date string. The date will be mapped to the current time zone. If you want to convert it to a localized string, use Date.toLocaleDateString instead.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.toDateString->Console.log
// Sun Jan 01 2023

Date.fromString("2023-01-01T00:00:00.00+08:00")->Date.toDateString->Console.log
// Sat Dec 31 2022

toISOString

RES

let toISOString: t => string

toISOString(date)

Converts a JavaScript date to a ISO 8601 string (YYYY-MM-DDTHH:mm:ss.sssZ). The date will be mapped to the UTC time.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+00:00")->Date.toISOString->Console.log
// 2023-01-01T00:00:00.000Z

Date.fromString("2023-01-01T00:00:00.00+08:00")->Date.toISOString->Console.log
// 2022-12-31T16:00:00.000Z

toJSON

RES

let toJSON: t => option<string>

toJSON(date)

Converts a JavaScript date to a string. If the date is valid, the function will return the same result as Date.toISOString. Invalid dates will return None.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+00:00")->Date.toJSON
// Some("2023-01-01T00:00:00.000Z")

Date.fromString("")->Date.toJSON
// None

toLocaleDateString

RES

let toLocaleDateString: t => string

toLocaleDateString(date)

Converts a JavaScript date to a localized date string. It will use the current locale.

Examples

RES
Date.make()->Date.toLocaleDateString->Console.log
// 2/19/2023

toLocaleDateStringWithLocale

RES

let toLocaleDateStringWithLocale: (t, string) => string

toLocaleDateStringWithLocale(date, locale)

Converts a JavaScript date to a localized date string. It will use the specified locale.

Examples

RES
Date.make()->Date.toLocaleDateStringWithLocale("en-US")->Console.log
// 2/19/2023

toLocaleDateStringWithLocaleAndOptions

RES

let toLocaleDateStringWithLocaleAndOptions: (t, string, localeOptions) => string

toLocaleDateStringWithLocaleAndOptions(date, locale, options)

Converts a JavaScript date to a localized date string. It will use the specified locale and formatting options.

Examples

RES
Date.make()->Date.toLocaleDateStringWithLocaleAndOptions("en-US", {dateStyle: #long})->Console.log
// February 19, 2023

Date.make()
->Date.toLocaleDateStringWithLocaleAndOptions("de", {hour: #"2-digit", minute: #"2-digit"})
->Console.log
// 19.2.2023, 15:40

Date.make()->Date.toLocaleDateStringWithLocaleAndOptions("de", {year: #numeric})->Console.log
// 2023

toLocaleString

RES

let toLocaleString: t => string

toLocaleString(date)

Converts a JavaScript date to a localized date-time string. It will use the current locale.

Examples

RES
Date.make()->Date.toLocaleString->Console.log
// 2/19/2023, 3:40:00 PM

toLocaleStringWithLocale

RES

let toLocaleStringWithLocale: (t, string) => string

toLocaleStringWithLocale(date, locale)

Converts a JavaScript date to a localized date-time string. It will use the specified locale.

Examples

RES
Date.make()->Date.toLocaleStringWithLocale("en-US")->Console.log
// 2/19/2023, 3:40:00 PM

toLocaleStringWithLocaleAndOptions

RES

let toLocaleStringWithLocaleAndOptions: (t, string, localeOptions) => string

toLocaleStringWithLocaleAndOptions(date, locale, options)

Converts a JavaScript date to a localized date-time string. It will use the specified locale and formatting options.

Examples

RES
Date.make()
->Date.toLocaleStringWithLocaleAndOptions("en", {dateStyle: #short, timeStyle: #short})
->Console.log
// 2/19/23, 3:40 PM

Date.make()
->Date.toLocaleStringWithLocaleAndOptions(
  "en",
  {
    era: #long,
    year: #numeric,
    month: #"2-digit",
    day: #"2-digit",
    hour: #numeric,
    timeZoneName: #short,
  },
)
->Console.log
// 02/19/2023 Anno Domini, 3 PM GMT+1

toLocaleTimeString

RES

let toLocaleTimeString: t => string

toLocaleTimeString(date)

Converts a JavaScript date to a localized time string. It will use the current locale.

Examples

RES
Date.make()->Date.toLocaleTimeString->Console.log
// 3:40:00 PM

toLocaleTimeStringWithLocale

RES

let toLocaleTimeStringWithLocale: (t, string) => string

toLocaleTimeStringWithLocale(date, locale)

Converts a JavaScript date to a localized time string. It will use the specified locale.

Examples

RES
Date.make()->Date.toLocaleTimeStringWithLocale("en-US")->Console.log
// 3:40:00 PM

toLocaleTimeStringWithLocaleAndOptions

RES

let toLocaleTimeStringWithLocaleAndOptions: (t, string, localeOptions) => string

toLocaleTimeStringWithLocaleAndOptions(date, locale, options)

Converts a JavaScript date to a localized time string. It will use the specified locale and formatting options.

Examples

RES
Date.make()->Date.toLocaleTimeStringWithLocaleAndOptions("en-US", {timeStyle: #long})->Console.log
// 3:40:00 PM GMT+1

Date.make()
->Date.toLocaleTimeStringWithLocaleAndOptions("de", {hour: #"2-digit", minute: #"2-digit"})
->Console.log
// 15:40

toString

RES

let toString: t => string

toString(date)

Converts a JavaScript date to a standard date time string. The date will be mapped to the current time zone. If you want to convert it to a localized string, use Date.toLocaleString instead.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.toString->Console.log
// Sun Jan 01 2023 00:00:00 GMT+0100 (Central European Standard Time)

Date.fromString("2023-06-01T00:00:00.00+01:00")->Date.toString->Console.log
// Thu Jun 01 2023 01:00:00 GMT+0200 (Central European Summer Time)

toTimeString

RES

let toTimeString: t => string

toTimeString(date)

Converts a JavaScript date to a standard time string. The date will be mapped to the current time zone. If you want to convert it to a localized string, use Date.toLocaleStimeString instead.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+01:00")->Date.toTimeString->Console.log
// 00:00:00 GMT+0100 (Central European Standard Time)

Date.fromString("2023-01-01T00:00:00.00+08:00")->Date.toTimeString->Console.log
// 17:00:00 GMT+0100 (Central European Standard Time)

toUTCString

RES

let toUTCString: t => string

toUTCString(date)

Converts a JavaScript date to date time string. The date will be mapped to the UTC time.

Examples

RES
Date.fromString("2023-01-01T00:00:00.00+00:00")->Date.toUTCString->Console.log
// Sun, 01 Jan 2023 00:00:00 GMT

Date.fromString("2023-01-01T00:00:00.00+08:00")->Date.toUTCString->Console.log
// Sat, 31 Dec 2022 16:00:00 GMT