Renamed to ad-si/Vectual. That is where the repository lives now. It has not been published as a package under the new name.
Versions published as adius/vectual still install under that name. 3 versions of 7 come from the new location (see their notes).
Helpers for working with elm/lang's Posix data type (Mostly copied from https://package.elm-lang.org/packages/rluiten/elm-TimeUtils)
Return True if year is a leap year.
Return the ISO day of the week. From Monday == 1, to Sunday == 7.
Return the ISO number of each month [1-12].
Return days in month for year and month.