parseUnitFromDate

Signature

parseUnitFromDate(value: string, unit: "dayOfWeek" | SmallestUnit<"year" | "month" | "week" | "day">, optionsArg?: { weekStartsOn?: "monday" | "sunday"; }): string

Return a specific date unit extracted from a PlainDate string.

• Extracts “year”, “month”, “day”, “week”, or “dayOfWeek” from a PlainDate.
• Returns zero-padded string for month and day.
• unit accepts the singular or plural name of a Temporal unit ("hour" or "hours"), as Temporal does; "dayOfWeek" has no plural.
• optionsArg must be an object or omitted: null or any other primitive returns "", as Temporal’s GetOptionsObject rejects it.
• Returns "" for invalid input.
• The "year" unit is written as Temporal writes a year: four digits ("2024", "0005"), or a sign and six digits outside 0000–9999 ("+010000", "-000005").

Parameters

Parameter	Type	Description
value	string	ISO PlainDate string
unit	"dayOfWeek" | SmallestUnit<"year" | "month" | "week" | "day">	unit to extract from the date

Options

optionsArg

How weeks are numbered

Option	Type	Default	Description
weekStartsOn?	"monday" | "sunday"	"monday"	The first day of the week, which sets how the "week" unit is numbered. "monday" gives the ISO 8601 week number, where week 1 holds the year’s first Thursday; "sunday" gives the UTS #35 week number with a Sunday first day and one minimal day, where week 1 holds 1 January. Any other value returns "", whatever the unit.

Returns

string representation of the requested unit or "" on invalid input

Examples

import { parseUnitFromDate } from "@northguild/gmt/plain/parse";

parseUnitFromDate("2024-03-15", "year") // "2024"

value

output

 

Source

plain/parse/parseUnitFromDate.ts