parseWeekFromZoned

Signature

parseWeekFromZoned(value: string, optionsArg?: { weekStartsOn?: "monday" | "sunday"; }): number | null

Return the week of the year for a given ISO 8601 zoned datetime string.

• "monday" is the ISO 8601 week of the week-year: week 1 is the week containing the first Thursday, so late-December days can be week 1 of the next year (a value on 2024-12-31 → 1). The result is 1–53.
• "sunday" is the UTS #35 week of the week-year with a Sunday first day and minimal days 1: week 1 is the Sunday-first week holding 1 January, so late-December days can be week 1 of the next year (2024-12-31 → 1, 2000-12-30 → 53). The result is 1–53.
• The week is read from the value’s own date on its own wall clock.
• Returns null for invalid input.

Parameters

Parameter	Type	Description
value	string	ISO zoned datetime string

Options

optionsArg

optional setting for the week’s first day

Option	Type	Default	Description
weekStartsOn?	"monday" | "sunday"	"monday"	The first day of the week, which sets how the week 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 null.

Returns

Week number (1-53), or null on invalid input

Examples

import { parseWeekFromZoned } from "@northguild/gmt/zoned/parse";

parseWeekFromZoned("2024-01-01T14:30:45.123+00:00[UTC]") // 1

value

output

 

Source

zoned/parse/parseWeekFromZoned.ts