Korbin Bickel

I was able to find a draft of the spec prior to finalization in PDF format. http://www.loc.gov/standards/datetime/iso-tc154-wg5_n0038_iso_wd_8601-1_2016-02-16.pdf Relevant section is 4.4.3.2 on page 23. So long as the final spec...

Same as java, multiply by 7 and add to days. Optionally, if only weeks is populated then `toISO()` could return in [PnnW] format as well. But it is still valid...

I don't think a separate `toISOWeeks` function makes sense, since most of the time it wouldn't be valid. Only when the current unit break down only has weeks in it....

> @icambron ISO8601 states that numbers in interval string must be positive integers. as('weeks') gives us a fractional value in general. I think we should truncate the value. P156.0000744047619W looks...

@vsubhuman , sorry about that. Give it a try now.