Struct minstant::Instant

pub struct Instant(/* private fields */);

A measurement of a monotonically nondecreasing clock. Similar to std::time::Instant but is faster and more accurate if TSC is available.

Implementations

impl Instant

pub const ZERO: Instant = _

A default Instant that can be seen as a fixed but random moment.

pub fn now() -> Instant

Returns an instant corresponding to “now”.

Examples

use minstant::Instant;

let now = Instant::now();

pub fn duration_since(&self, earlier: Instant) -> Duration

Returns the amount of time elapsed from another instant to this one, or zero duration if that instant is later than this one.

Panics

Previously we panicked if earlier was later than self. Currently this method saturates to follow the behavior of the standard library. Future versions may reintroduce the panic in some circumstances.

Examples

use std::time::Duration;
use std::thread::sleep;

use minstant::Instant;

let now = Instant::now();
sleep(Duration::new(1, 0));
let new_now = Instant::now();
println!("{:?}", new_now.duration_since(now));
println!("{:?}", now.duration_since(new_now)); // 0ns

pub fn checked_duration_since(&self, earlier: Instant) -> Option<Duration>

Returns the amount of time elapsed from another instant to this one, or None if that instant is later than this one.

Examples

use std::time::Duration;
use std::thread::sleep;

use minstant::Instant;

let now = Instant::now();
sleep(Duration::new(1, 0));
let new_now = Instant::now();
println!("{:?}", new_now.checked_duration_since(now));
println!("{:?}", now.checked_duration_since(new_now)); // None

pub fn saturating_duration_since(&self, earlier: Instant) -> Duration

Returns the amount of time elapsed from another instant to this one, or zero duration if that instant is later than this one.

Examples

use std::time::Duration;
use std::thread::sleep;

use minstant::Instant;

let now = Instant::now();
sleep(Duration::new(1, 0));
let new_now = Instant::now();
println!("{:?}", new_now.saturating_duration_since(now));
println!("{:?}", now.saturating_duration_since(new_now)); // 0ns

pub fn elapsed(&self) -> Duration

Returns the amount of time elapsed since this instant was created.

Panics

This function may panic if the current time is earlier than this instant, which is something that can happen if an Instant is produced synthetically.

Examples

use std::time::Duration;
use std::thread::sleep;

use minstant::Instant;

let instant = Instant::now();
let three_secs = Duration::from_secs(3);
sleep(three_secs);
assert!(instant.elapsed() >= three_secs);

pub fn checked_add(&self, duration: Duration) -> Option<Instant>

Returns Some(t) where t is the time self + duration if t can be represented as Instant (which means it’s inside the bounds of the underlying data structure), None otherwise.

pub fn checked_sub(&self, duration: Duration) -> Option<Instant>

Returns Some(t) where t is the time self - duration if t can be represented as Instant (which means it’s inside the bounds of the underlying data structure), None otherwise.

pub fn as_unix_nanos(&self, anchor: &Anchor) -> u64

Convert interal clocking counter into a UNIX timestamp represented as the nanoseconds elapsed from UNIX_EPOCH.

Anchor contains the necessary calibration data for conversion. Typically, initializing an Anchor takes about 50 nano seconds, so try to reuse it for a batch of Instant.

Examples

use std::time::UNIX_EPOCH;
use minstant::{Instant, Anchor};

let anchor = Anchor::new();
let instant = Instant::now();

let expected = UNIX_EPOCH.elapsed().unwrap().as_nanos();
assert!((instant.as_unix_nanos(&anchor) as i64 - expected as i64).abs() < 1_000_000);

Trait Implementations

impl Add<Duration> for Instant

type Output = Instant

The resulting type after applying the + operator.

fn add(self, other: Duration) -> Instant

Performs the + operation.

impl AddAssign<Duration> for Instant

fn add_assign(&mut self, other: Duration)

Performs the += operation.

impl Clone for Instant

fn clone(&self) -> Instant

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Instant

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Instant> for Atomic

Available on crate feature atomic and target_has_atomic="64" only.

fn from(instant: Instant) -> Self

Converts to this type from the input type.

impl Hash for Instant

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Instant

fn cmp(&self, other: &Instant) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for Instant

fn eq(&self, other: &Instant) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Instant

fn partial_cmp(&self, other: &Instant) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Sub<Duration> for Instant

type Output = Instant

The resulting type after applying the - operator.

fn sub(self, other: Duration) -> Instant

Performs the - operation.

impl Sub for Instant

fn sub(self, other: Instant) -> Duration

Returns the amount of time elapsed from another instant to this one, or zero duration if that instant is later than this one.

Panics

Previously we panicked if other was later than self. Currently this method saturates to follow the behavior of the standard library. Future versions may reintroduce the panic in some circumstances.

type Output = Duration

The resulting type after applying the - operator.

impl SubAssign<Duration> for Instant

fn sub_assign(&mut self, other: Duration)

Performs the -= operation.

impl Copy for Instant

impl Eq for Instant

impl StructuralPartialEq for Instant