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[Chrono][docsrs]: Timezone-aware date and time handling
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Chrono aims to provide all functionality needed to do correct operations on dates and times in the
* The [`DateTime`](https://docs.rs/chrono/latest/chrono/struct.DateTime.html) type is timezone-aware
by default, with separate timezone-naive types.
* Operations that may produce an invalid or ambiguous date and time return `Option` or
* Configurable parsing and formatting with an `strftime` inspired date and time formatting syntax.
the current timezone of the OS.
* Types and operations are implemented to be reasonably efficient.
Timezone data is not shipped with chrono by default to limit binary sizes. Use the companion crate
full timezone support.
## Documentation
## Limitations
* Only the proleptic Gregorian calendar (i.e. extended to support older dates) is supported.
* Date types are limited to about +/- 262,000 years from the common epoch.
* Time types are limited to nanosecond accuracy.
* Leap seconds can be represented, but Chrono does not fully support them.
See [Leap Second Handling](https://docs.rs/chrono/latest/chrono/naive/struct.NaiveTime.html#leap-second-handling).
## Crate features
Default features:
* `alloc`: Enable features that depend on allocation (primarily string formatting).
* `std`: Enables functionality that depends on the standard library. This is a superset of `alloc`
and adds interoperation with standard library types and traits.
* `clock`: Enables reading the local timezone (`Local`). This is a superset of `now`.
* `now`: Enables reading the system time (`now`).
* `wasmbind`: Interface with the JS Date API for the `wasm32` target.
Optional features:
* `serde`: Enable serialization/deserialization via [serde].
* `rkyv`: Deprecated, use the `rkyv-*` features.
* `rkyv-16`: Enable serialization/deserialization via [rkyv], using 16-bit integers for integral `*size` types.
* `rkyv-32`: Enable serialization/deserialization via [rkyv], using 32-bit integers for integral `*size` types.
* `rkyv-64`: Enable serialization/deserialization via [rkyv], using 64-bit integers for integral `*size` types.
* `rkyv-validation`: Enable rkyv validation support using `bytecheck`.
* `arbitrary`: Construct arbitrary instances of a type with the Arbitrary crate.
* `unstable-locales`: Enable localization. This adds various methods with a `_localized` suffix.
The implementation and API may change or even be removed in a patch release. Feedback welcome.
* `oldtime`: This feature no longer has any effect; it used to offer compatibility with the `time` 0.1 crate.
Note: The `rkyv{,-16,-32,-64}` features are mutually exclusive.
## Rust version requirements
The Minimum Supported Rust Version (MSRV) is currently **Rust 1.61.0**.
The MSRV is explicitly tested in CI. It may be bumped in minor releases, but this is not done
lightly.
## License
This project is licensed under either of
at your option.