Time
The Storm standard library contains basic functionality for measuring time. This API is currently aimed at measuring elapsed time, not to handle clocks, time zones, etc.
The functionality is provided by the two types core.Moment and
core.Duration. The first, Moment represents a moment in time. The Moment is
represented as a time-stamp based on some high-resolution clock in the system. A Duration is then
the difference between two Moments, that is a measurement of how much time has elapsed between two
points in time. Since the Moment has no defined anchor in time, it is usually not meaningful to
speak about the absolute value of a a moment. They are only meaningful to create Durations.
Moment
As previously mentioned, a core.Moment represents some point in time as measured by a
high-resolution clock in the current system. This clock is typically not related to wall-time clock
in a meaningful way. This means that a Moment is good to measure time at a high precision, but it
is not a good way to communicate points in time to others, as their clock may have a different
zero-point.
The type is a value that contains a single 64-bit time value, measured in nanoseconds. When created,
Moment captures the current time and stores it. As such, the operation that is often interesting
for Moment is to just create it and do arithmetics on it with Durations.
It is possible to subtract two Moments to create a Duration that represents the time elapsed
between them. It is also possible to add a Duration to a Moment to create a new Moment that
represents a time in the future. Similarly, Durations can be subtracted from Moments to
represent a time in the past. It is also possible to compare Moments to establish their causual
relation.
You can use the static function resolution to ask Moment about the actual resolution of the
timestamps on the current system (i.e., Moment:resolution() in Basic Storm).
Duration
The value core.Duration represents a difference between two Moments expressed in
nanoseconds. The time value is accessible using any one of the following functions:
-
core.Long inNs()Get duration in nanoseconds.
-
core.Long inUs()Get the duration in microseconds.
-
core.Long inMs()Get the duration in milliseconds.
-
core.Long inS()Get the duration in seconds.
-
core.Long inMin()Get the duration in minutes.
-
core.Long inH()Get the duration in hours.
Creating a Duration using its default constructor creates the duration of zero. To create other
values, one of the helper functions h, min, s, ms, or us can be used. They create a
Duration initialized to the specified timespan in the specified unit. Basic Storm also allows
using these functions as units. As such, one can write:
Duration x = 5 min; sleep(2 s);
As with Moment, the Duration class provides many arithmetic operators for addition and
subtraction of durations. It is also possible to scale a duration with an Int or Float factor
(with * and /), computing the ratio between two Durations using /, repeating a Duration
using %, finding minimum and maximum values using min and max, and comparing them. All of
these operators work as one would expect when representing a Duration as a number.
The library also provides the ability to sleep for a specified duration:
-
void sleep(core.Duration d)Sleep for the specified duration. Do not expect more than ms precision.