Crate t2t_core 

Time values: points on the wall and monotonic clocks, counter readings, and the spans between them.

Each timeline has its own point, and each kind of count its own span. A point minus a point is a span, a point plus a span is a point, and points of two timelines never mix:

Point	Timeline	Span
Timestamp	the wall clock, from the Unix epoch	Timedelta
TaiTimestamp	International Atomic Time, from 1970 TAI	Timedelta
Uptime	the monotonic clock, from near boot	Timedelta
RawUptime	the monotonic clock at the hardware’s rate	Timedelta
BootUptime	the boot clock, suspensions counted	Timedelta
Tickstamp	a hardware counter, from its own origin	Tickdelta

Every point and span is an i64, and its operators saturate at the ends of the range rather than overflow, each with a checked_* twin. Every value has a spelling, which Display writes and FromStr reads back.

Types

• Points. Timestamp and TaiTimestamp name a moment another machine names too; Uptime, RawUptime and BootUptime never step; a Tickstamp is a counter’s reading. TimePoint is what they share, for code generic over them.
• Spans. Timedelta counts nanoseconds and Tickdelta a counter’s ticks; a TickRate turns one into the other.
• Views. Timed is a value and the stamp it was captured with; UtcDateTime is a timestamp read as a date and a time of day.
• Refusals. ParseTimestampError, ParseTaiTimestampError, ParseTimedeltaError, ParseTickdeltaError and ParseTickRateError for a spelling that does not read; OutOfRangeError for a time another type cannot hold.

Examples

use t2t_core::{Timed, Timedelta, Timestamp};

let stale: Timedelta = "1s".parse()?;
let captured = Timestamp::from_secs(1_700_000_000);
let sample = Timed::new(captured, 101_u64);

assert!(sample.elapsed(captured + Timedelta::from_millis(1_500)) > stale, "stale by now");

Crate Features

None is on by default, and nothing reaches the operating system unless std is named; what std adds is on 64-bit Linux and macOS.

Feature	Adds
std	SystemTime conversions
serde	every value’s spelling, and the serde modules for counts in a named unit
schemars	JsonSchema for every value with a spelling; turns serde on
zerocopy	the zerocopy traits each type can honour, native-endian
chrono-04	conversions to and from chrono 0.4’s DateTime and TimeDelta
jiff-02	conversions to and from jiff 0.2’s Timestamp and SignedDuration
time-03	conversions to and from time 0.3’s OffsetDateTime and Duration

Modules

serdeserde

How a time crosses to a config file, a log or a peer.

Structs

BootUptime

A point on the boot clock, in nanoseconds since boot, the machine’s suspensions counted.

OutOfRangeError

Why a time does not fit the type it was converted to: a negative span for a Duration, or a value past what a count of nanoseconds holds.

ParseTaiTimestampError

Why a string is not a TaiTimestamp.

ParseTickRateError

Why a string is not a TickRate.

ParseTickdeltaError

Why a string is not a Tickdelta, nor a Tickstamp.

ParseTimedeltaError

Why a string is not a Timedelta, nor a point counted from boot.

ParseTimestampError

Why a string is not a Timestamp.

RawUptime

A point on the monotonic clock at the hardware’s own rate, in nanoseconds since an origin near boot.

TaiTimestamp

A point on International Atomic Time, in nanoseconds since 1970-01-01T00:00:00 TAI.

TickRate

How many ticks a counter advances in a second: what turns Tickdelta into a Timedelta and back.

Tickdelta

A signed span of counter ticks: how far apart two Tickstamps are.

Tickstamp

A point on a hardware counter, in ticks since an origin the hardware chose.

Timed

A value T and the stamp S its writer captured it with.

Timedelta

A signed span of nanoseconds: how far apart two points on one timeline are.

Timestamp

A point on the wall clock, in nanoseconds since the Unix epoch.

Uptime

A point on the monotonic clock, in nanoseconds since an origin near boot.

UtcDateTime

A point on the wall clock read as a date and a time of day: UTC, in the proleptic Gregorian calendar.

Traits

TimePoint

A point on one timeline, carried as a count of its unit since the timeline’s origin, with the span between two of them.