tap Method

Overload 1

Creates a new stream with a side effect, similar to the RxJS tap operator.

This method allows you to perform actions or side effects whenever the state emits a value, without altering the value itself. It is useful for tasks like logging, debugging, or triggering external operations in response to emitted values

@param observer: Partial<Observer<T>>
A partial observer with lifecycle methods (next, error, complete)

@returns this
The instance of the current state, allowing for method chaining

API

tap(observer: Partial<Observer<T>>): this;

Example

import {state} from '@bitfiber/rx';
 
const log = state<number>(0, s => s
  // Performs a tap callback each time the state emits new data
  .tap({
    next: id => console.log(id),
    error: error => console.log(error),
  }));

Overload 2

Creates a new stream with a side effect, similar to the RxJS tap operator.

@param next: (value: T) => void
A function that takes the emitted value and performs a side effect

@returns this
The instance of the current state, allowing for method chaining

API

tap(next: (value: T) => void): this;

Example

import {state} from '@bitfiber/rx';
 
const log = state<number>(0, s => s
  // Performs a tap callback each time the state emits new data
  .tap(id => console.log(id)));

effect Comparison