Crate time

Feature flags

This crate exposes a number of features. These can be enabled or disabled as shown in Cargo’s documentation. Features are disabled by default unless otherwise noted.

Reliance on a given feature is always indicated alongside the item definition.

• std (enabled by default, implicitly enables alloc)

  This enables a number of features that depend on the standard library.

• alloc (enabled by default via std)

  Enables a number of features that require the ability to dynamically allocate memory.

• macros

  Enables macros that provide compile-time verification of values and intuitive syntax.

• formatting (implicitly enables std)

  Enables formatting of most structs.

• parsing

  Enables parsing of most structs.

• local-offset (implicitly enables std)

  This feature enables a number of methods that allow obtaining the system’s UTC offset.

• large-dates

  By default, only years within the ±9999 range (inclusive) are supported. If you need support for years outside this range, consider enabling this feature; the supported range will be increased to ±999,999.

  Note that enabling this feature has some costs, as it means forgoing some optimizations. Ambiguities may be introduced when parsing that would not otherwise exist.

• serde

  Enables serde support for all types except Instant.

• serde-human-readable (implicitly enables serde, formatting, and parsing)

  Allows serde representations to use a human-readable format. This is determined by the serializer, not the user. If this feature is not enabled or if the serializer requests a non-human-readable format, a format optimized for binary representation will be used.

  Libraries should never enable this feature, as the decision of what format to use should be up to the user.

• serde-well-known (implicitly enables serde-human-readable)

  This feature flag is deprecated and will be removed in a future breaking release. Use the serde-human-readable feature instead.

  Enables support for serializing and deserializing well-known formats using serde’s #[with] attribute.

• rand

  Enables rand support for all types.

• quickcheck (implicitly enables alloc)

  Enables quickcheck support for all types except Instant.

• wasm-bindgen

  Enables wasm-bindgen support for converting JavaScript dates, as well as obtaining the UTC offset from JavaScript.