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Notification

deprecated

Represents a push-based event or value that an Observable can emit. This class is particularly useful for operators that manage notifications, like materialize, dematerialize, observeOn, and others. Besides wrapping the actual delivered value, it also annotates it with metadata of, for instance, what type of push message it is (next, error, or complete).

@deprecated

It is NOT recommended to create instances of Notification directly. Rather, try to create POJOs matching the signature outlined in ObservableNotification. For example: { kind: 'N', value: 1 }, { kind: 'E', error: new Error('bad') }, or { kind: 'C' }. Will be removed in v8.

class Notification<T> {

constructor(kind: "N", value?: T);

constructor(

kind: "E",

value: undefined,

error: any,

);

constructor(kind: "C");

readonly error?: any;

readonly hasValue: boolean;

readonly kind: "N" | "E" | "C";

readonly value?: T | undefined;

accept(

next: (value: T) => void,

error: (err: any) => void,

complete: () => void,

): void;

accept(next: (value: T) => void, error: (err: any) => void): void;

accept(next: (value: T) => void): void;

accept(observer: PartialObserver<T>): void;

do(

next: (value: T) => void,

error: (err: any) => void,

complete: () => void,

): void;

do(next: (value: T) => void, error: (err: any) => void): void;

do(next: (value: T) => void): void;

observe(observer: PartialObserver<T>): void;

toObservable(): Observable<T>;

static private completeNotification;

static createComplete(): Notification<never> & CompleteNotification;

static createError(err?: any): Notification<never> & ErrorNotification;

static createNext<T>(value: T): Notification<T> & NextNotification<T>;

}

§Type Parameters

T

§Constructors

new Notification(kind: "N", value?: T)

Creates a "Next" notification object.

@param kind

Always 'N'

@param value

The value to notify with if observed.

@deprecated

Internal implementation detail. Use {@link Notification#createNext | createNext} instead.

new Notification(kind: "E", value: undefined, error: any)

Creates an "Error" notification object.

@param kind

Always 'E'

@param value

Always undefined

@param error

The error to notify with if observed.

@deprecated

Internal implementation detail. Use {@link Notification#createError | createError} instead.

new Notification(kind: "C")

Creates a "completion" notification object.

@param kind

Always 'C'

@deprecated

Internal implementation detail. Use {@link Notification#createComplete | createComplete} instead.

§Properties

error: any

hasValue: boolean

A value signifying that the notification will "next" if observed. In truth, This is really synonymous with just checking kind === "N".

kind: "N" | "E" | "C"

value: T | undefined

§Methods

accept(next: (value: T) => void, error: (err: any) => void, complete: () => void): void deprecated

Executes a notification on the appropriate handler from a list provided. If a handler is missing for the kind of notification, nothing is called and no error is thrown, it will be a noop.

@param next

A next handler

@param error

An error handler

@param complete

A complete handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

accept(next: (value: T) => void, error: (err: any) => void): void deprecated

Executes a notification on the appropriate handler from a list provided. If a handler is missing for the kind of notification, nothing is called and no error is thrown, it will be a noop.

@param next

A next handler

@param error

An error handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

accept(next: (value: T) => void): void deprecated

Executes the next handler if the Notification is of kind "N". Otherwise this will not error, and it will be a noop.

@param next

The next handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

accept(observer: PartialObserver<T>): void deprecated

Executes the appropriate handler on a passed observer given the kind of notification. If the handler is missing it will do nothing. Even if the notification is an error, if there is no error handler on the observer, an error will not be thrown, it will noop.

@param observer

The observer to notify.

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

do(next: (value: T) => void, error: (err: any) => void, complete: () => void): void deprecated

Executes a notification on the appropriate handler from a list provided. If a handler is missing for the kind of notification, nothing is called and no error is thrown, it will be a noop.

@param next

A next handler

@param error

An error handler

@param complete

A complete handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

do(next: (value: T) => void, error: (err: any) => void): void deprecated

Executes a notification on the appropriate handler from a list provided. If a handler is missing for the kind of notification, nothing is called and no error is thrown, it will be a noop.

@param next

A next handler

@param error

An error handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

do(next: (value: T) => void): void deprecated

Executes the next handler if the Notification is of kind "N". Otherwise this will not error, and it will be a noop.

@param next

The next handler

@deprecated

Replaced with {@link Notification#observe | observe}. Will be removed in v8.

observe(observer: PartialObserver<T>): void

Executes the appropriate handler on a passed observer given the kind of notification. If the handler is missing it will do nothing. Even if the notification is an error, if there is no error handler on the observer, an error will not be thrown, it will noop.

@param observer

The observer to notify.

toObservable(): Observable<T> deprecated

Returns a simple Observable that just delivers the notification represented by this Notification instance.

@deprecated

Will be removed in v8. To convert a Notification to an Observable, use of and dematerialize: of(notification).pipe(dematerialize()).

§Static Properties

completeNotification

§Static Methods

createComplete(): Notification<never> & CompleteNotification deprecated

A shortcut to create a Notification instance of the type complete.

@return

The valueless "complete" Notification.

@deprecated

It is NOT recommended to create instances of Notification directly. Rather, try to create POJOs matching the signature outlined in ObservableNotification. For example: { kind: 'N', value: 1 }, { kind: 'E', error: new Error('bad') }, or { kind: 'C' }. Will be removed in v8.

createError(err?: any): Notification<never> & ErrorNotification deprecated

A shortcut to create a Notification instance of the type error from a given error.

@return

The "error" Notification representing the argument.

@deprecated

It is NOT recommended to create instances of Notification directly. Rather, try to create POJOs matching the signature outlined in ObservableNotification. For example: { kind: 'N', value: 1 }, { kind: 'E', error: new Error('bad') }, or { kind: 'C' }. Will be removed in v8.

createNext<T>(value: T): Notification<T> & NextNotification<T> deprecated

A shortcut to create a Notification instance of the type next from a given value.

@param value

The next value.

@return

The "next" Notification representing the argument.

@deprecated

It is NOT recommended to create instances of Notification directly. Rather, try to create POJOs matching the signature outlined in ObservableNotification. For example: { kind: 'N', value: 1 }, { kind: 'E', error: new Error('bad') }, or { kind: 'C' }. Will be removed in v8.