time.minutes-between

def minutes_between(start_date: str, start_time: str, end_date: str, end_time: str) -> int

from fune.time.minutes_between import minutes_between  # time.minutes-between@^1

from .dates_add_days import epoch_day_from_iso  ← from dates.add-days ^1.0.0 · built alongside by fune


def _minute_of_day(time: str) -> int:
    ok = (
        isinstance(time, str)
        and len(time) == 5
        and time[2] == ":"
        and all("0" <= time[i] <= "9" for i in (0, 1, 3, 4))
    )
    hours = int(time[0:2]) if ok else -1
    minutes = int(time[3:5]) if ok else -1
    if not ok or hours > 23 or minutes > 59:
        raise ValueError('"%s" is not a time of day (HH:MM, 00:00 to 23:59)' % (time,))
    return hours * 60 + minutes


def minutes_between(start_date: str, start_time: str, end_date: str, end_time: str) -> int:
    """Minutes from one local date and time to another: the difference between
    two wall-clock readings. It knows nothing of time zones or daylight saving,
    so across a clock change it differs from real elapsed time by the change.
    """
    days = epoch_day_from_iso(end_date) - epoch_day_from_iso(start_date)
    return days * 1440 + _minute_of_day(end_time) - _minute_of_day(start_time)

Install

fune build

With that line in your source, in a Python project (language python in fune.project), fune build resolves it and its 1 dependency, pins them in fune.lock, downloads only the Python package of each, and builds the code above into your project’s .fune/build, one readable file per capability with a header linking back here. Or pin a range in fune.project and build in one step:

fune add time.minutes-between

The manifest, vectors and README with only the Python implementation. Install it without the registry with fune add ./time.minutes-between-1.0.0-python.fune, or fetch it from a terminal with fune pull time.minutes-between@1.0.0:python.

The whole function, every language, is one file too: time.minutes-between-1.0.0.fune, 8,862 bytes, sha256 f28512233b8908b71542c3178abccb2281cb736b93ba1f13ac1eede9c71e9386. It installs into a project of any language.

# fune: before time.minutes-between

# fune: after time.minutes-between

# fune: replace dates.add-days in time.minutes-between

# fune: step time.minutes-between after <n|label>

More from the author

**Local wall-clock time, no time zones.** Both times are read off the same clock on the wall, and the answer is the difference between those readings. It does not know about daylight saving: in the UK, 00:30 to 03:30 on 29 March 2026 is 180 minutes here though only 120 minutes passed, because the clocks went forward at 01:00; on 25 October 2026 the same readings are 180 here and 240 in reality. Payroll and time-and-attendance rules differ on which of those to pay, so this capability does not pick one silently: if real elapsed time matters, convert both instants to UTC with a time zone database first and subtract those.

Times are strictly HH:MM, 24-hour, 00:00 to 23:59. "24:00", "9:00" and "5pm" are errors rather than guesses; the end of a day is 00:00 on the next date.

Files