serp-datetime

UTC date/time written in the Serpentine subset, over serp-time for the clock. Dt is a year/month/day/hour/minute/second dataclass — UTC only, second resolution; timezones (zoneinfo) come later per the roadmap.

API

• make(y, mo, d, h, mi, s) / make_date(y, mo, d) — validated construction (ValueError with CPython-style messages).
• now_utc() — current UTC time via serp_time.time().
• to_unix(dt) -> int / from_unix(ts) -> Dt — proleptic Gregorian, days-from-civil algorithm (valid for any year).
• iso_format(dt) — YYYY-MM-DDTHH:MM:SS; parse_iso(s) accepts a date or dateTtime (space separator ok).
• weekday(dt) — 0 = Monday; day_of_year(dt); is_leap(y); days_in_month(y, m).
• add_days(dt, n), add_seconds(dt, n), diff_seconds(a, b) — timedelta-style arithmetic.

Stdlib classes

date, datetime and timedelta mirror the stdlib constructors with CPython 3.11 validation messages, isoformat(), str/repr parity, comparisons and +/- arithmetic.

• date.fromisoformat(s) / datetime.fromisoformat(s) — naive values only; the T separator is optional (a space works), a trailing Z is accepted and ignored, fractional seconds are parsed to microseconds. UTC offsets are not supported.
• datetime.fromtimestamp(ts) — a UTC (not local) datetime, a divergence.
• datetime.utcnow() / utcnow() — current UTC time.

Install

serp add serp-datetime
pip install serp-datetime