Struct core::time::Duration

pub struct Duration {
    secs: u64,
    nanos: Nanoseconds,
}

A Duration type to represent a span of time, typically used for system timeouts.

Each Duration is composed of a whole number of seconds and a fractional part represented in nanoseconds. If the underlying system does not support nanosecond-level precision, APIs binding a system timeout will typically round up the number of nanoseconds.

Durations implement many common traits, including Add, Sub, and other ops traits. It implements Default by returning a zero-length Duration.

Examples

use std::time::Duration;

let five_seconds = Duration::new(5, 0);
let five_seconds_and_five_nanos = five_seconds + Duration::new(0, 5);

assert_eq!(five_seconds_and_five_nanos.as_secs(), 5);
assert_eq!(five_seconds_and_five_nanos.subsec_nanos(), 5);

let ten_millis = Duration::from_millis(10);

Formatting Duration values

Duration intentionally does not have a Display impl, as there are a variety of ways to format spans of time for human readability. Duration provides a Debug impl that shows the full precision of the value.

The Debug output uses the non-ASCII “µs” suffix for microseconds. If your program output may appear in contexts that cannot rely on full Unicode compatibility, you may wish to format Duration objects yourself or use a crate to do so.

Fields

secs: u64

nanos: Nanoseconds

Implementations

impl Duration

pub const SECOND: Duration = _

🔬This is a nightly-only experimental API. (duration_constants #57391)

The duration of one second.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::SECOND, Duration::from_secs(1));

pub const MILLISECOND: Duration = _

🔬This is a nightly-only experimental API. (duration_constants #57391)

The duration of one millisecond.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::MILLISECOND, Duration::from_millis(1));

pub const MICROSECOND: Duration = _

🔬This is a nightly-only experimental API. (duration_constants #57391)

The duration of one microsecond.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::MICROSECOND, Duration::from_micros(1));

pub const NANOSECOND: Duration = _

🔬This is a nightly-only experimental API. (duration_constants #57391)

The duration of one nanosecond.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::NANOSECOND, Duration::from_nanos(1));

pub const ZERO: Duration = _

A duration of zero time.

Examples

use std::time::Duration;

let duration = Duration::ZERO;
assert!(duration.is_zero());
assert_eq!(duration.as_nanos(), 0);

pub const MAX: Duration = _

The maximum duration.

May vary by platform as necessary. Must be able to contain the difference between two instances of Instant or two instances of SystemTime. This constraint gives it a value of about 584,942,417,355 years in practice, which is currently used on all platforms.

Examples

use std::time::Duration;

assert_eq!(Duration::MAX, Duration::new(u64::MAX, 1_000_000_000 - 1));

pub const fn new(secs: u64, nanos: u32) -> Duration

Creates a new Duration from the specified number of whole seconds and additional nanoseconds.

If the number of nanoseconds is greater than 1 billion (the number of nanoseconds in a second), then it will carry over into the seconds provided.

Panics

This constructor will panic if the carry from the nanoseconds overflows the seconds counter.

Examples

use std::time::Duration;

let five_seconds = Duration::new(5, 0);

pub const fn from_secs(secs: u64) -> Duration

Creates a new Duration from the specified number of whole seconds.

Examples

use std::time::Duration;

let duration = Duration::from_secs(5);

assert_eq!(5, duration.as_secs());
assert_eq!(0, duration.subsec_nanos());

pub const fn from_millis(millis: u64) -> Duration

Creates a new Duration from the specified number of milliseconds.

Examples

use std::time::Duration;

let duration = Duration::from_millis(2569);

assert_eq!(2, duration.as_secs());
assert_eq!(569_000_000, duration.subsec_nanos());

pub const fn from_micros(micros: u64) -> Duration

Creates a new Duration from the specified number of microseconds.

Examples

use std::time::Duration;

let duration = Duration::from_micros(1_000_002);

assert_eq!(1, duration.as_secs());
assert_eq!(2000, duration.subsec_nanos());

pub const fn from_nanos(nanos: u64) -> Duration

Creates a new Duration from the specified number of nanoseconds.

Examples

use std::time::Duration;

let duration = Duration::from_nanos(1_000_000_123);

assert_eq!(1, duration.as_secs());
assert_eq!(123, duration.subsec_nanos());

pub const fn is_zero(&self) -> bool

Returns true if this Duration spans no time.

Examples

use std::time::Duration;

assert!(Duration::ZERO.is_zero());
assert!(Duration::new(0, 0).is_zero());
assert!(Duration::from_nanos(0).is_zero());
assert!(Duration::from_secs(0).is_zero());

assert!(!Duration::new(1, 1).is_zero());
assert!(!Duration::from_nanos(1).is_zero());
assert!(!Duration::from_secs(1).is_zero());

pub const fn as_secs(&self) -> u64

Returns the number of whole seconds contained by this Duration.

The returned value does not include the fractional (nanosecond) part of the duration, which can be obtained using subsec_nanos.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_secs(), 5);

To determine the total number of seconds represented by the Duration including the fractional part, use as_secs_f64 or as_secs_f32

pub const fn subsec_millis(&self) -> u32

Returns the fractional part of this Duration, in whole milliseconds.

This method does not return the length of the duration when represented by milliseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one thousand).

Examples

use std::time::Duration;

let duration = Duration::from_millis(5432);
assert_eq!(duration.as_secs(), 5);
assert_eq!(duration.subsec_millis(), 432);

pub const fn subsec_micros(&self) -> u32

Returns the fractional part of this Duration, in whole microseconds.

This method does not return the length of the duration when represented by microseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one million).

Examples

use std::time::Duration;

let duration = Duration::from_micros(1_234_567);
assert_eq!(duration.as_secs(), 1);
assert_eq!(duration.subsec_micros(), 234_567);

pub const fn subsec_nanos(&self) -> u32

Returns the fractional part of this Duration, in nanoseconds.

This method does not return the length of the duration when represented by nanoseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one billion).

Examples

use std::time::Duration;

let duration = Duration::from_millis(5010);
assert_eq!(duration.as_secs(), 5);
assert_eq!(duration.subsec_nanos(), 10_000_000);

pub const fn as_millis(&self) -> u128

Returns the total number of whole milliseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_millis(), 5730);

pub const fn as_micros(&self) -> u128

Returns the total number of whole microseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_micros(), 5730023);

pub const fn as_nanos(&self) -> u128

Returns the total number of nanoseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_nanos(), 5730023852);

pub const fn checked_add(self, rhs: Duration) -> Option<Duration>

Checked Duration addition. Computes self + other, returning None if overflow occurred.

Examples

Basic usage:

use std::time::Duration;

assert_eq!(Duration::new(0, 0).checked_add(Duration::new(0, 1)), Some(Duration::new(0, 1)));
assert_eq!(Duration::new(1, 0).checked_add(Duration::new(u64::MAX, 0)), None);

pub const fn saturating_add(self, rhs: Duration) -> Duration

Saturating Duration addition. Computes self + other, returning Duration::MAX if overflow occurred.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::new(0, 0).saturating_add(Duration::new(0, 1)), Duration::new(0, 1));
assert_eq!(Duration::new(1, 0).saturating_add(Duration::new(u64::MAX, 0)), Duration::MAX);

pub const fn checked_sub(self, rhs: Duration) -> Option<Duration>

Checked Duration subtraction. Computes self - other, returning None if the result would be negative or if overflow occurred.

Examples

Basic usage:

use std::time::Duration;

assert_eq!(Duration::new(0, 1).checked_sub(Duration::new(0, 0)), Some(Duration::new(0, 1)));
assert_eq!(Duration::new(0, 0).checked_sub(Duration::new(0, 1)), None);

pub const fn saturating_sub(self, rhs: Duration) -> Duration

Saturating Duration subtraction. Computes self - other, returning Duration::ZERO if the result would be negative or if overflow occurred.

Examples

use std::time::Duration;

assert_eq!(Duration::new(0, 1).saturating_sub(Duration::new(0, 0)), Duration::new(0, 1));
assert_eq!(Duration::new(0, 0).saturating_sub(Duration::new(0, 1)), Duration::ZERO);

pub const fn checked_mul(self, rhs: u32) -> Option<Duration>

Checked Duration multiplication. Computes self * other, returning None if overflow occurred.

Examples

Basic usage:

use std::time::Duration;

assert_eq!(Duration::new(0, 500_000_001).checked_mul(2), Some(Duration::new(1, 2)));
assert_eq!(Duration::new(u64::MAX - 1, 0).checked_mul(2), None);

pub const fn saturating_mul(self, rhs: u32) -> Duration

Saturating Duration multiplication. Computes self * other, returning Duration::MAX if overflow occurred.

Examples

#![feature(duration_constants)]
use std::time::Duration;

assert_eq!(Duration::new(0, 500_000_001).saturating_mul(2), Duration::new(1, 2));
assert_eq!(Duration::new(u64::MAX - 1, 0).saturating_mul(2), Duration::MAX);

pub const fn checked_div(self, rhs: u32) -> Option<Duration>

Checked Duration division. Computes self / other, returning None if other == 0.

Examples

Basic usage:

use std::time::Duration;

assert_eq!(Duration::new(2, 0).checked_div(2), Some(Duration::new(1, 0)));
assert_eq!(Duration::new(1, 0).checked_div(2), Some(Duration::new(0, 500_000_000)));
assert_eq!(Duration::new(2, 0).checked_div(0), None);

pub fn as_secs_f64(&self) -> f64

Returns the number of seconds contained by this Duration as f64.

The returned value does include the fractional (nanosecond) part of the duration.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.as_secs_f64(), 2.7);

pub fn as_secs_f32(&self) -> f32

Returns the number of seconds contained by this Duration as f32.

The returned value does include the fractional (nanosecond) part of the duration.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.as_secs_f32(), 2.7);

pub fn from_secs_f64(secs: f64) -> Duration

Creates a new Duration from the specified number of seconds represented as f64.

Panics

This constructor will panic if secs is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let res = Duration::from_secs_f64(0.0);
assert_eq!(res, Duration::new(0, 0));
let res = Duration::from_secs_f64(1e-20);
assert_eq!(res, Duration::new(0, 0));
let res = Duration::from_secs_f64(4.2e-7);
assert_eq!(res, Duration::new(0, 420));
let res = Duration::from_secs_f64(2.7);
assert_eq!(res, Duration::new(2, 700_000_000));
let res = Duration::from_secs_f64(3e10);
assert_eq!(res, Duration::new(30_000_000_000, 0));
// subnormal float
let res = Duration::from_secs_f64(f64::from_bits(1));
assert_eq!(res, Duration::new(0, 0));
// conversion uses rounding
let res = Duration::from_secs_f64(0.999e-9);
assert_eq!(res, Duration::new(0, 1));

pub fn from_secs_f32(secs: f32) -> Duration

Creates a new Duration from the specified number of seconds represented as f32.

Panics

This constructor will panic if secs is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let res = Duration::from_secs_f32(0.0);
assert_eq!(res, Duration::new(0, 0));
let res = Duration::from_secs_f32(1e-20);
assert_eq!(res, Duration::new(0, 0));
let res = Duration::from_secs_f32(4.2e-7);
assert_eq!(res, Duration::new(0, 420));
let res = Duration::from_secs_f32(2.7);
assert_eq!(res, Duration::new(2, 700_000_048));
let res = Duration::from_secs_f32(3e10);
assert_eq!(res, Duration::new(30_000_001_024, 0));
// subnormal float
let res = Duration::from_secs_f32(f32::from_bits(1));
assert_eq!(res, Duration::new(0, 0));
// conversion uses rounding
let res = Duration::from_secs_f32(0.999e-9);
assert_eq!(res, Duration::new(0, 1));

pub fn mul_f64(self, rhs: f64) -> Duration

Multiplies Duration by f64.

Panics

This method will panic if result is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.mul_f64(3.14), Duration::new(8, 478_000_000));
assert_eq!(dur.mul_f64(3.14e5), Duration::new(847_800, 0));

pub fn mul_f32(self, rhs: f32) -> Duration

Multiplies Duration by f32.

Panics

This method will panic if result is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.mul_f32(3.14), Duration::new(8, 478_000_641));
assert_eq!(dur.mul_f32(3.14e5), Duration::new(847800, 0));

pub fn div_f64(self, rhs: f64) -> Duration

Divide Duration by f64.

Panics

This method will panic if result is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.div_f64(3.14), Duration::new(0, 859_872_611));
assert_eq!(dur.div_f64(3.14e5), Duration::new(0, 8_599));

pub fn div_f32(self, rhs: f32) -> Duration

Divide Duration by f32.

Panics

This method will panic if result is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
// note that due to rounding errors result is slightly
// different from 0.859_872_611
assert_eq!(dur.div_f32(3.14), Duration::new(0, 859_872_580));
assert_eq!(dur.div_f32(3.14e5), Duration::new(0, 8_599));

pub fn div_duration_f64(self, rhs: Duration) -> f64

🔬This is a nightly-only experimental API. (div_duration #63139)

Divide Duration by Duration and return f64.

Examples

#![feature(div_duration)]
use std::time::Duration;

let dur1 = Duration::new(2, 700_000_000);
let dur2 = Duration::new(5, 400_000_000);
assert_eq!(dur1.div_duration_f64(dur2), 0.5);

pub fn div_duration_f32(self, rhs: Duration) -> f32

🔬This is a nightly-only experimental API. (div_duration #63139)

Divide Duration by Duration and return f32.

Examples

#![feature(div_duration)]
use std::time::Duration;

let dur1 = Duration::new(2, 700_000_000);
let dur2 = Duration::new(5, 400_000_000);
assert_eq!(dur1.div_duration_f32(dur2), 0.5);

impl Duration

pub fn try_from_secs_f32(secs: f32) -> Result<Duration, TryFromFloatSecsError>

The checked version of from_secs_f32.

This constructor will return an Err if secs is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let res = Duration::try_from_secs_f32(0.0);
assert_eq!(res, Ok(Duration::new(0, 0)));
let res = Duration::try_from_secs_f32(1e-20);
assert_eq!(res, Ok(Duration::new(0, 0)));
let res = Duration::try_from_secs_f32(4.2e-7);
assert_eq!(res, Ok(Duration::new(0, 420)));
let res = Duration::try_from_secs_f32(2.7);
assert_eq!(res, Ok(Duration::new(2, 700_000_048)));
let res = Duration::try_from_secs_f32(3e10);
assert_eq!(res, Ok(Duration::new(30_000_001_024, 0)));
// subnormal float:
let res = Duration::try_from_secs_f32(f32::from_bits(1));
assert_eq!(res, Ok(Duration::new(0, 0)));

let res = Duration::try_from_secs_f32(-5.0);
assert!(res.is_err());
let res = Duration::try_from_secs_f32(f32::NAN);
assert!(res.is_err());
let res = Duration::try_from_secs_f32(2e19);
assert!(res.is_err());

// the conversion uses rounding with tie resolution to even
let res = Duration::try_from_secs_f32(0.999e-9);
assert_eq!(res, Ok(Duration::new(0, 1)));

// this float represents exactly 976562.5e-9
let val = f32::from_bits(0x3A80_0000);
let res = Duration::try_from_secs_f32(val);
assert_eq!(res, Ok(Duration::new(0, 976_562)));

// this float represents exactly 2929687.5e-9
let val = f32::from_bits(0x3B40_0000);
let res = Duration::try_from_secs_f32(val);
assert_eq!(res, Ok(Duration::new(0, 2_929_688)));

// this float represents exactly 1.000_976_562_5
let val = f32::from_bits(0x3F802000);
let res = Duration::try_from_secs_f32(val);
assert_eq!(res, Ok(Duration::new(1, 976_562)));

// this float represents exactly 1.002_929_687_5
let val = f32::from_bits(0x3F806000);
let res = Duration::try_from_secs_f32(val);
assert_eq!(res, Ok(Duration::new(1, 2_929_688)));

pub fn try_from_secs_f64(secs: f64) -> Result<Duration, TryFromFloatSecsError>

The checked version of from_secs_f64.

This constructor will return an Err if secs is negative, overflows Duration or not finite.

Examples

use std::time::Duration;

let res = Duration::try_from_secs_f64(0.0);
assert_eq!(res, Ok(Duration::new(0, 0)));
let res = Duration::try_from_secs_f64(1e-20);
assert_eq!(res, Ok(Duration::new(0, 0)));
let res = Duration::try_from_secs_f64(4.2e-7);
assert_eq!(res, Ok(Duration::new(0, 420)));
let res = Duration::try_from_secs_f64(2.7);
assert_eq!(res, Ok(Duration::new(2, 700_000_000)));
let res = Duration::try_from_secs_f64(3e10);
assert_eq!(res, Ok(Duration::new(30_000_000_000, 0)));
// subnormal float
let res = Duration::try_from_secs_f64(f64::from_bits(1));
assert_eq!(res, Ok(Duration::new(0, 0)));

let res = Duration::try_from_secs_f64(-5.0);
assert!(res.is_err());
let res = Duration::try_from_secs_f64(f64::NAN);
assert!(res.is_err());
let res = Duration::try_from_secs_f64(2e19);
assert!(res.is_err());

// the conversion uses rounding with tie resolution to even
let res = Duration::try_from_secs_f64(0.999e-9);
assert_eq!(res, Ok(Duration::new(0, 1)));
let res = Duration::try_from_secs_f64(0.999_999_999_499);
assert_eq!(res, Ok(Duration::new(0, 999_999_999)));
let res = Duration::try_from_secs_f64(0.999_999_999_501);
assert_eq!(res, Ok(Duration::new(1, 0)));
let res = Duration::try_from_secs_f64(42.999_999_999_499);
assert_eq!(res, Ok(Duration::new(42, 999_999_999)));
let res = Duration::try_from_secs_f64(42.999_999_999_501);
assert_eq!(res, Ok(Duration::new(43, 0)));

// this float represents exactly 976562.5e-9
let val = f64::from_bits(0x3F50_0000_0000_0000);
let res = Duration::try_from_secs_f64(val);
assert_eq!(res, Ok(Duration::new(0, 976_562)));

// this float represents exactly 2929687.5e-9
let val = f64::from_bits(0x3F68_0000_0000_0000);
let res = Duration::try_from_secs_f64(val);
assert_eq!(res, Ok(Duration::new(0, 2_929_688)));

// this float represents exactly 1.000_976_562_5
let val = f64::from_bits(0x3FF0_0400_0000_0000);
let res = Duration::try_from_secs_f64(val);
assert_eq!(res, Ok(Duration::new(1, 976_562)));

// this float represents exactly 1.002_929_687_5
let val = f64::from_bits(0x3_FF00_C000_0000_000);
let res = Duration::try_from_secs_f64(val);
assert_eq!(res, Ok(Duration::new(1, 2_929_688)));

Trait Implementations

impl Add<Duration> for Duration

type Output = Duration

The resulting type after applying the + operator.

fn add(self, rhs: Duration) -> Duration

Performs the + operation.

impl AddAssign<Duration> for Duration

fn add_assign(&mut self, rhs: Duration)

Performs the += operation.

impl Clone for Duration

fn clone(&self) -> Duration

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Duration

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

Formats the value using the given formatter.

impl Default for Duration

fn default() -> Duration

Returns the “default value” for a type.

impl Div<u32> for Duration

type Output = Duration

The resulting type after applying the / operator.

fn div(self, rhs: u32) -> Duration

Performs the / operation.

impl DivAssign<u32> for Duration

fn div_assign(&mut self, rhs: u32)

Performs the /= operation.

impl Eq for Duration

fn assert_receiver_is_total_eq(&self)

impl Hash for Duration

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

Feeds this value into the given Hasher.

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

Feeds a slice of this type into the given Hasher.

impl Mul<Duration> for u32

type Output = Duration

The resulting type after applying the * operator.

fn mul(self, rhs: Duration) -> Duration

Performs the * operation.

impl Mul<u32> for Duration

type Output = Duration

The resulting type after applying the * operator.

fn mul(self, rhs: u32) -> Duration

Performs the * operation.

impl MulAssign<u32> for Duration

fn mul_assign(&mut self, rhs: u32)

Performs the *= operation.

impl Ord for Duration

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq<Duration> for Duration

fn eq(&self, other: &Duration) -> 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<Duration> for Duration

fn partial_cmp(&self, other: &Duration) -> 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 Duration

type Output = Duration

The resulting type after applying the - operator.

fn sub(self, rhs: Duration) -> Duration

Performs the - operation.

impl SubAssign<Duration> for Duration

fn sub_assign(&mut self, rhs: Duration)

Performs the -= operation.

impl<'a> Sum<&'a Duration> for Duration

fn sum<I: Iterator<Item = &'a Duration>>(iter: I) -> Duration

Method which takes an iterator and generates Self from the elements by “summing up” the items.

impl Sum<Duration> for Duration

fn sum<I: Iterator<Item = Duration>>(iter: I) -> Duration

Method which takes an iterator and generates Self from the elements by “summing up” the items.

impl Copy for Duration

impl StructuralEq for Duration

impl StructuralPartialEq for Duration