systimes

The systimes module implements an alternative way to represent a timestamp + timezone. Nim's standard library uses the DateTime type to represent the same thing. There are two important differences between DateTime and SysTime:

• SysTime is immutable.
• SysTime only stores a times.Time and a times.Timezone, meaning that individual calendar fields like year, month and so on are never stored.

Some things to keep in mind:

• When the calendar fields are accessed several times for the same object, there is a performance penalty when using SysTime since they must be computed at every access.
• Many procs are faster for SysTime. Notably all procs involving Duration since they no longer require timezone information.
• Some procs are slower for SysTime. Notably all procs involving TimeInterval.
• SysTime is much more space effecient.

The name SysTime comes from the SysTime class from Phobos, which uses a similiar representation for timestamp + timezone.

Usage

import systimes, times
let x = sysnow()
let y = initSysTime(01, mJan, 2000, 12, 00, 00, utc())
doAssert x > y
doAssert x < y + 10.years
echo y # 2000-01-01T12:00:00Z

systimes exposes a very similiar API for SysTime as the times module does for DateTime. Notable differences are listed in the table below. Generated docs are available here.