Date Math Calculator

• datemath_add — Adds years/months/days to date. years/months are applied together with end-of-month clamping — e.g. 2026-01-31 + 1 month = 2026-02-28, not an overflowed 2026-03
• datemath_age — Age in whole years as of asOf (optional, defaults to the current UTC date). A Feb-29 birthDate is treated as falling on March 1 in a non-leap asOf year.
• datemath_businessdays — Counts days in [from, to] (inclusive on both ends) whose weekday is in weekdays (default mon-fri) and which aren't in holidays.
• datemath_dayofweek — Day of the week for date: both the weekday name and its ISO 8601 weekday number (1=Monday..7=Sunday).
• datemath_diff — Day difference between two YYYY-MM-DD dates: to minus from, in whole days. Negative if to is before from.
• datemath_leapyear — Checks whether year is a leap year in the Gregorian calendar.

No long description beyond the summary.