Relative dates
Package:
DATETIME_PACKAGE. Registered bycreateEngine(); for a slimmer engine, register it explicitly (see choosing packages).
A relative date names a day by its relation to today rather than by its calendar number, the way you would say tomorrow or next friday out loud. Each resolves against the current date, so it computes here rather than being asserted.
nowtodaytomorrowyesterdaynext fridaylast monday