Class Duration
extends Object implements Comparable
A Duration, capturing relative times.
Durations can be negative.
Durations are limited to ~292 years (signed 64 bit nanoseconds).
Class summary
| constructor --h/int= --m/int= --s/int= --ms/int= --us/int= --ns/int= | Constructs a duration of h hours, m minutes, ms milliseconds, us microseconds, and ns nanoseconds. |
|---|---|
| constructor ns_/int | Constructs a duration of ns_ nanoseconds. |
Constructors
Constructs a duration of h hours, m minutes, ms milliseconds, us microseconds, and ns nanoseconds.
constructor ns_/int
Constructs a duration of ns_ nanoseconds.
Statics
The number of microseconds per hour.
The number of microseconds per millisecond.
The number of microseconds per minute.
The number of microseconds per second.
The number of milliseconds per hour.
The number of milliseconds per minute.
The number of milliseconds per second.
The number of nanoseconds per hour.
The number of nanoseconds per microsecond.
The number of nanoseconds per millisecond.
The number of nanoseconds per minute.
The number of nanoseconds per second.
Calls the given block and measures the duration of the call.
Aliases
Stopwatch: DartDatedifference: JavaScript
Parses a duration from the given string.
Accepts string of the form '-?(\d+([.]\d+)?(h|m|ms|us|ns)][ ]?)+'.
Only seconds, ms, and us may have a fractional part.
Spaces are not allowed inside units (like 'u s') but otherwise all spaces are ignored.
Units may only be used once.
Examples
print (Duration.parse "1h2m3s") // >> 1h2m3s
print (Duration.parse "1h2m3.4s") // >> 1h2m3.4s
print (Duration.parse "1h2m3.4s5ms") // >> 1h2m3.4s5ms
print (Duration.parse "1h2m3.4s5ms6us") // >> 1h2m3.4s5ms6us
print (Duration.parse "66m") // >> 1h6m
print (Duration.parse "-1h") // >> -1h
The number of seconds per hour.
The number of seconds per minute.
This operation is equivalent to Time.to-now which is preferred, unless the developer wants to emphasize the Duration type.
Examples
main:
// In this example, we assume the time is 2021-04-21 15:30:35 UTC.
time := Time.utc --year=2021 --month=04 --day=21 --h=17 --m=45 --s=35b
print
Duration.until time // >> 2h15m0s
time = Time.utc --year=2021 --month=04 --day=21 --h=14 --m=45 --s=35b
print
Duration.until time // >> -45m0s
Methods
Subtracts this duration from the other duration.
Examples
t_12s := Duration --s=12
t_5s := Duration --s=5
print t_12s - t_5s // >> 7s
print t_5s - t_12s // >> -7s
Negates this duration.
Examples
t_5s := Duration --s=5
print -t_5s // >> -5s
print -(-t_5) // >> 5s
Multiplies this duration with the factor.
Examples
t_5s := Duration --s=5
print t_5s * 2 // 10s
print t_5s * -3 // -15s
print 5 * t_5s // Error, num's * does not know Duration!
Divides the duration by the factor.
Example
t_9s := Duration --s=9
print t_9s / 3 // >> 3s
Adds this duration to the other duration.
Examples
t_12s := Duration --s=12
t_5s := Duration --s=5
print t_12s + t_5s // >> 17s
t_42ns := Duration --ns=42
print t_12s + t_42ns // >> 12.000000042s
Whether this duration is less than the other.
Examples
d_5ns := Duration --ns=5
d_12s := Duration --s=12
d_5ns < d_5ns // => false
d_12s < d_5ns // => false
d_5ns < d_12s // => true
Whether this duration is less than or equal to the other.
d_5ns := Duration --ns=5
d_12s := Duration --s=12
d_5ns <= d_5ns // => true
d_5ns <= d_12s // => true
d_12s <= d_5ns // => false
Whether this duration is equal to the other.
Examples
d_5ns := Duration --ns=5
d_12s := Duration --s=12
d_5ns == d_5ns // => true
d_12s == t_5ns // => false
Whether this duration is greater than the other.
Examples
d_5ns := Duration --ns=5
d_12s := Duration --s=12
d_5ns > d_5ns // => false
d_5ns > d_12s // => false
d_12s > d_5ns // => true
Whether this duration is greater than or equal to the other.
Examples
d_5ns := Duration --ns=5
d_12s := Duration --s=12
d_5ns >= d_12s // => false
d_5ns >= d_5ns // => true
d_12s >= d_5ns // => true
Calls the given block periodically.
Advanced
Ensures that two executions of the block are always spaced out by *at least* this duration. At the end of every call of the block sleeps the remaining amount of this duration.
If an execution took longer than the period, skips one cycle. For example, if the block was supposed to run every 5ms, but the the first execution took 7ms, then this function sleeps 3ms, before it calls the block again at the next cycle (10ms).
This function may drift. If the start of the block is delayed (because of imprecision, or because the system was busy), then the subsequent executions will never catch up with the original schedule.