Enum Zone 

pub enum Zone {
    Utc,
    Local,
    Fixed(i32),
    Rules(Arc<Rules>),
}

A time zone: how many seconds its clocks are ahead of UTC at each moment. Zone::Local is the platform’s local zone, which follows summer time; Zone::posix, Zone::tzif and Zone::named read a zone’s rules; Zone::Fixed never changes.

use rich_interact::datetime::{Date, DateTime, Time, Zone};

// Central Europe: an hour ahead in winter, two in summer.
let cet = Zone::posix("CET-1CEST,M3.5.0,M10.5.0/3").unwrap();
let winter = DateTime::new(Date::new(2026, 1, 15), Time::new(12, 0, 0));
let summer = DateTime::new(Date::new(2026, 7, 15), Time::new(12, 0, 0));
assert_eq!(cet.offset_at(winter.to_unix(&Zone::Utc)), 3600);
assert_eq!(cet.offset_at(summer.to_unix(&Zone::Utc)), 7200);

Variants

Utc

Coordinated Universal Time.

Local

The platform’s local zone, as it is now configured (TZ, /etc/localtime, the system’s setting).

Fixed(i32)

Always this many seconds ahead of UTC (behind if negative).

Rules(Arc<Rules>)

A zone’s rules, read by Zone::posix, Zone::tzif or Zone::named.

Implementations

impl Zone

pub fn offset_at(&self, unix: i64) -> i32

How many seconds the zone’s clocks are ahead of UTC at unix (seconds since 1970-01-01 00:00 UTC).

pub fn posix(rule: &str) -> Result<Zone, String>

The zone a POSIX TZ rule describes: "CET-1CEST,M3.5.0,M10.5.0/3", "EST5EDT,M3.2.0,M11.1.0", "<+0330>-3:30", "UTC0". A summer time with no days given starts and ends on the United States’.

pub fn tzif(bytes: &[u8]) -> Result<Zone, String>

The zone in a TZif file (/usr/share/zoneinfo/Europe/Berlin): its transitions, and the rule in its footer for the years after.

pub fn named(name: &str) -> Result<Zone, String>

The zone named name in the zoneinfo database ("Europe/London"), read from $TZDIR or /usr/share/zoneinfo; an error where there is no such file (as on Windows).

Trait Implementations

impl Clone for Zone

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Zone

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

Formats the value using the given formatter.

impl PartialEq for Zone

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Zone