Use Subject

import { useSubject } from '@vueuse/rxjs'
import { Subject } from 'rxjs'

const subject = new Subject()

// setup()
const subjectRef = useSubject(subject)

// Changes to subjectRef.value will be pushed to the subject
subjectRef.value = 'new value'

// Values emitted by the subject will update subjectRef
subject.next('from subject')

import { useSubject } from '@vueuse/rxjs'
import { BehaviorSubject } from 'rxjs'

const subject = new BehaviorSubject('initial')

// setup()
const subjectRef = useSubject(subject) // Ref<string>, not Ref<string | undefined>
console.log(subjectRef.value) // 'initial'

import { useSubject } from '@vueuse/rxjs'
import { Subject } from 'rxjs'

const subject = new Subject()

// setup()
const subjectRef = useSubject(subject, {
  onError: (err) => {
    console.log(err.message) // "oops"
  },
},)

export interface UseSubjectOptions<I = undefined> extends Omit<
  UseObservableOptions<I>,
  "initialValue"
> {}
export declare function useSubject<H>(
  subject: BehaviorSubject<H>,
  options?: UseSubjectOptions,
): Ref<H>
export declare function useSubject<H>(
  subject: Subject<H>,
  options?: UseSubjectOptions,
): Ref<H | undefined>