API Interval

Interval

Concepts first: read Core Concepts before this page.

Signatures below are shown as the library declares them. From a script that imports it, every type and enum name takes your import alias: t.DateTime, t.Overflow.REJECT, t.Exchange.NYSE. A bare DateTime will not compile.

An Interval is a half-open span of instants, [FromMS, ToMS). Half-open so that consecutive intervals tile a timeline without overlapping at the join.

The type

Interval

type

A half-open span of instants, [FromMS, ToMS).

Field	Declared as	Meaning
FromMS	int FromMS = 0	Inclusive start, Unix milliseconds.
ToMS	int ToMS = 0	Exclusive end, Unix milliseconds.

Members

	Summary
abuts	Whether two intervals meet exactly end to start without overlapping: the condition under which they can be joined into one without a hole or a double count.
contains	Whether an instant falls inside this interval.
duration	The length of this interval in milliseconds.
encloses	Whether this interval wholly contains another.
equals	Whether two intervals have identical endpoints.
gap	The empty span between two intervals that neither overlap nor touch.
intersection	The overlapping part of two intervals.
is_empty	Whether this interval contains no instants at all.
overlaps	Whether two intervals share any instant.
to_iso	This interval in ISO-8601 interval form, "start/end", with both endpoints in UTC.

Reference

abuts

Interval.abuts(Interval other)

Whether two intervals meet exactly end to start without overlapping: the condition under which they can be joined into one without a hole or a double count.

Parameter	Meaning
other	The second Interval.

Returns   true when one ends precisely where the other begins..

contains

Interval.contains(int unix_ms)

Whether an instant falls inside this interval. The interval is half-open, [FromMS, ToMS), so back-to-back intervals never both claim the same instant.

Parameter	Meaning
unix_ms	Unix timestamp in milliseconds.

Returns   true when FromMS <= unix_ms < ToMS..

duration

Interval.duration()

The length of this interval in milliseconds.

Returns   Milliseconds spanned; zero when empty..

encloses

Interval.encloses(Interval other)

Whether this interval wholly contains another.

Parameter	Meaning
other	The inner Interval.

Returns   true when other lies entirely within this..

equals

Interval.equals(Interval other)

Whether two intervals have identical endpoints.

Parameter	Meaning
other	The second Interval.

Returns   true when both endpoints match..

gap

Interval.gap(Interval other)

The empty span between two intervals that neither overlap nor touch.

Parameter	Meaning
other	The second Interval.

Returns   The gap Interval, or na when they overlap or abut..

intersection

Interval.intersection(Interval other)

The overlapping part of two intervals.

Parameter	Meaning
other	The second Interval.

Returns   The shared Interval, or na when they do not overlap..

is_empty

Interval.is_empty()

Whether this interval contains no instants at all.

Returns   true when the end is not after the start..

overlaps

Interval.overlaps(Interval other)

Whether two intervals share any instant. Half-open, so intervals that merely touch do not overlap.

Parameter	Meaning
other	The second Interval.

Returns   true when they intersect..

to_iso

Interval.to_iso()

This interval in ISO-8601 interval form, "start/end", with both endpoints in UTC.

Returns   A string such as "2026-08-21T13:30:00Z/2026-08-21T20:00:00Z"..

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