Module peprock.datetime.period

Datetime period model.

Examples

>>> period = Period(
...     start=datetime.datetime(2022, 1, 1, 12, 0),
...     end=datetime.datetime(2022, 1, 2, 12, 0),
... )
>>> period.duration
datetime.timedelta(days=1)
>>> period.midpoint
datetime.datetime(2022, 1, 2, 0, 0)
>>> datetime.datetime(2022, 1, 1) in period
False
>>> period.start in period
True
>>> period.midpoint in period
True
>>> period.end in period
True
>>> datetime.datetime(2022, 1, 3) in period
False
>>> period in period
True
>>> Period(
...     start=datetime.datetime(2022, 1, 1),
...     end=datetime.datetime(2022, 1, 3),
... ) in period
False

Classes

class Period (start: datetime.datetime, end: datetime.datetime)

Datetime period supporting arithmetic operations.

Expand source code

@dataclasses.dataclass(frozen=True)
class Period(
    collections.abc.Container["Period | datetime.datetime"],
):
    """Datetime period supporting arithmetic operations."""

    start: datetime.datetime
    end: datetime.datetime

    @functools.cached_property
    def duration(self: Self) -> datetime.timedelta:
        """Return duration of period."""
        return self.end - self.start

    @functools.cached_property
    def midpoint(self: Self) -> datetime.datetime:
        """Return midpoint of period."""
        return self.start + self.duration / 2

    def __contains__(self: Self, item: object) -> bool:
        """Return True if item is in period."""
        match item:
            case Period():
                # noinspection PyUnresolvedReferences
                return self.start <= item.start and item.end <= self.end
            case datetime.datetime():
                # noinspection PyTypeChecker
                return self.start <= item <= self.end

        msg: str = f"expected peprock.datetime.Period | datetime.datetime, got {item!r}"
        raise TypeError(msg)

Ancestors

• collections.abc.Container

Class variables

var end : datetime.datetime

var start : datetime.datetime

Instance variables

var duration

Return duration of period.

Expand source code

def __get__(self, instance, owner=None):
    if instance is None:
        return self
    if self.attrname is None:
        raise TypeError(
            "Cannot use cached_property instance without calling __set_name__ on it.")
    try:
        cache = instance.__dict__
    except AttributeError:  # not all objects have __dict__ (e.g. class defines slots)
        msg = (
            f"No '__dict__' attribute on {type(instance).__name__!r} "
            f"instance to cache {self.attrname!r} property."
        )
        raise TypeError(msg) from None
    val = cache.get(self.attrname, _NOT_FOUND)
    if val is _NOT_FOUND:
        val = self.func(instance)
        try:
            cache[self.attrname] = val
        except TypeError:
            msg = (
                f"The '__dict__' attribute on {type(instance).__name__!r} instance "
                f"does not support item assignment for caching {self.attrname!r} property."
            )
            raise TypeError(msg) from None
    return val

var midpoint

Return midpoint of period.

Expand source code

def __get__(self, instance, owner=None):
    if instance is None:
        return self
    if self.attrname is None:
        raise TypeError(
            "Cannot use cached_property instance without calling __set_name__ on it.")
    try:
        cache = instance.__dict__
    except AttributeError:  # not all objects have __dict__ (e.g. class defines slots)
        msg = (
            f"No '__dict__' attribute on {type(instance).__name__!r} "
            f"instance to cache {self.attrname!r} property."
        )
        raise TypeError(msg) from None
    val = cache.get(self.attrname, _NOT_FOUND)
    if val is _NOT_FOUND:
        val = self.func(instance)
        try:
            cache[self.attrname] = val
        except TypeError:
            msg = (
                f"The '__dict__' attribute on {type(instance).__name__!r} instance "
                f"does not support item assignment for caching {self.attrname!r} property."
            )
            raise TypeError(msg) from None
    return val