std::time

Status: experimental

Wall-clock and monotonic time facilities.

Items

Item	Signature	Description
Instant	type Instant	A monotonic clock reading in nanoseconds: now(), elapsed(), elapsed_ms(), duration_since(earlier), later - earlier answering the Duration between them, + / - a Duration, and ordering.
Duration	type Duration	A span of nanoseconds: from_nanos / from_micros / from_millis / from_secs / from_secs_f64, the matching as_* accessors, +, -, and ordering.
SystemTime	type SystemTime	Wall-clock point-in-time.
CivilTime	type CivilTime	Calendar fields interpreted only with an explicit location.
CivilResolution	type CivilResolution	Explicit unique, gap, or fold result of resolving civil fields.
Location	type Location	Immutable IANA or fixed-offset time-zone location: lookup(name) (an IANA name, or "Local"), local() (the zone the system runs in: TZ, then the platform setting, else UTC), utc(), fixed(offset_seconds); name(), civil(unix_ms), resolve(civil).
Time	type Time	A wall-clock instant with the location it is read in: now(), from_unix / from_unix_ms / from_unix_nanos, parse_rfc3339 (keeps the written offset), format_rfc3339, civil(), in_location / utc, + / - a Duration, and a - b answering the Duration between two instants.
sleep	fn sleep(ms: i64) -> ()	Suspends the current goroutine for a Duration, or for an integer count of milliseconds.
after	fn after(d: time::Duration) -> Receiver<i64>	A Receiver that yields once after Duration, so a deadline composes with select and while let the way any other channel does.
sleep_ctx	fn sleep_ctx(ctx: context::Context, ms: i64) -> bool	Sleeps unless the context fires first; false when it cancelled the wait.
__sleep_ns	builtin __sleep_ns	Internal: suspends the current goroutine for a nanosecond count; the lowering of sleep and sleep_ctx.
__sleep_ns_ctx	builtin __sleep_ns_ctx	Internal: context-aware nanosecond sleep; the lowering of sleep_ctx that wakes early when the context fires.
now	fn now() -> i64	Wall-clock milliseconds since the Unix epoch; Instant::now() reads the monotonic clock.
format_rfc3339	fn format_rfc3339(ms: i64) -> Result<String, errors::Error>	Formats a SystemTime in RFC 3339 (YYYY-MM-DDTHH:MM:SSZ).
format_in	fn format_in(layout: String, unix_ms: i64, location: time::Location) -> Result<String, errors::Error>	Formats an instant in an explicit civil-time location.
add_date	fn add_date(unix_ms: i64, location: time::Location, years: i64, months: i64, days: i64) -> Result<i64, errors::Error>	Adds calendar units and rejects ambiguous or nonexistent results.
parse_rfc3339	fn parse_rfc3339(text: String) -> Result<i64, errors::Error>	Parses an RFC 3339 timestamp into a SystemTime.
freeze	fn freeze(ms: i64) -> ()	freeze(ms) - pin the wall clock at ms since the epoch, so a test over anything time-dependent - a token's expiry, a rate-limit window, a cache's TTL - reads a clock it controls. The monotonic clock and sleep are untouched: this pins what the program is told the time is, not how long anything takes.
advance	fn advance(ms: i64) -> i64	advance(ms) -> i64 - move a frozen wall clock forward and answer the new reading. Freezes at the current reading first when it is not already frozen.
unfreeze	fn unfreeze() -> ()	unfreeze() - return to the real wall clock.
is_frozen	fn is_frozen() -> bool	is_frozen() -> bool - whether the wall clock is pinned.
now_ms	fn now_ms() -> i64	Wall-clock milliseconds since the Unix epoch.
now_nanos	fn now_nanos() -> i64	Wall-clock nanoseconds since the Unix epoch.
unix_ms	fn unix_ms() -> i64	Current Unix time in milliseconds.
monotonic_ms	fn monotonic_ms() -> i64	Monotonic clock reading in milliseconds.
monotonic_nanos	fn monotonic_nanos() -> i64	Monotonic clock reading in nanoseconds.
since_ms	fn since_ms(start_ms: i64) -> i64	Milliseconds elapsed since an earlier monotonic reading.