Recursive Rx

recrx.js

const pageSize = 10

const getPage = page => {

    const pageContent = _.range(0, pageSize).map(v => v + (page * pageSize))
      
    if(page == 9) {

        return Rx.Observable.just({
            nextPage: null,
            page: pageContent
        })
    }

    return Rx.Observable.just({
        nextPage: page + 1,
        page: pageContent
    })
}

getPage(0)
    .expand(result => {

        if(!result.nextPage) {
            return Rx.Observable.empty()
        }
        return getPage(result.nextPage)
    })
    .scan((acc, page) => {
        return acc.concat(page.page)
    }, [])
    .last()
    .subscribe(x => console.log(x))