macro_observer_derive

Helper macro to implement a few traits required for a observer.

Traits you still have to implement to get a observer

• RxObserver

Traits Implemented

• WithPrimaryCategory: Sets the associated type to PrimaryCategoryObserver
• ObserverInput: Sets the associated type In to the value of the #[rx_in(...)] attribute, or to Never (Infallible) if missing. Also sets the associated InError type to the value of the #[rx_in_error(...)] attribute, or to Never if missing.
• UpgradeableObserver: By default. It implements UpgradeableObserver by wrapping the subject into a ObserverSubscriber. This implementation can be opted out with the #[rx_does_not_upgrade_to_observer_subscriber] attribute to provide a manual implementation. Other preset implementations can be used with the #[rx_upgrades_to(...)] attribute.

Attributes

All attributes are prefixed with rx_ for easy auto-complete access.

• #[rx_in(...)] (optional, default: Never): Defines the input type of the subscriber
• #[rx_in_error(...)] (optional, default: Never): Defines the input error type of the subscriber
• #[rx_does_not_upgrade_to_observer_subscriber] (optional): Opts out the default UpgradeableObserver implementation which just wraps the Subject in a ObserverSubscriber when used as a destination for an Observable to prevent upstream from unsubscribing the entire Subject.
• #[rx_upgrades_to(...)] (optional, accepts: self, observer_subscriber): Defines a preset implementation for UpgradeableObserver
  • self: Upgraded version is itself, causing it to be unsubscribed when upstream is unsubscribed when used as an observables destination.
  • observer_subscriber: Upgraded version is itself wrapped in ObserverSubscriber, causing it to not be unsubscribed when upstream is unsubscribed when used as an observables destination.

See Also

• RxExecutor - Derive macro for Executors.
• RxObservable - Derive macro for Observables.
• RxOperator - Derive macro for Operators.
• RxScheduler - Derive macro for Schedulers.
• RxSubject - Derive macro for Subjects.
• RxSubscriber - Derive macro for Subscribers.
• RxSubscription - Derive macro for Subscriptions.
• RxWork - Derive macro for schedulable work.

Expanding the proc macro

In case you want to inspect the output of the proc macro.

If you haven't installed cargo-expand yet, install it first:

cargo install cargo-expand

Then expand the macro output:

cargo expand -p rx_core_observable_interval