xs:duration does not support weeks

[aheissenberger]

The ISO 8601 standard allows to use Weeks but not combining them with other units.
The current implementation of the new browser Date API Temporal allows weeks to be combined with other units.

Example Duration P1W

fontoxpath/src/expressions/dataTypes/valueTypes/DayTimeDuration.ts

Lines 94 to 109 in d5ac004

	DayTimeDuration.fromString = (dayTimeDurationString: string): DayTimeDuration | null => {
	const regex = /^(-)?P(\d+Y)?(\d+M)?(\d+D)?(?:T(\d+H)?(\d+M)?(\d+(\.\d*)?S)?)?$/;
	const match = regex.exec(dayTimeDurationString);
	if (!match) {
	return null;
	}
	const isPositive = !match[1];
	const days = match[4] ? parseInt(match[4], 10) : 0;
	const hours = match[5] ? parseInt(match[5], 10) : 0;
	const minutes = match[6] ? parseInt(match[6], 10) : 0;
	const seconds = match[7] ? parseInt(match[7], 10) : 0;
	const secondFraction = match[8] ? parseFloat(match[8]) : 0;
	return DayTimeDuration.fromParts(days, hours, minutes, seconds, secondFraction, isPositive);