13.4.7 - combineLatest

将两个 Obserable 中最新发出的数据流进行组合成新的数据流，以数组的形式发出。和当前最新的进行组合

import { combineLatest, timer } from "rxjs"
const firstTimer = timer(0, 1000) // emit 0, 1, 2... after every second, starting from now
const secondTimer = timer(500, 1000) // emit 0, 1, 2... after every second, starting 0,5s from now
combineLatest(firstTimer, secondTimer).subscribe(console.log)
// [0, 0] after 0.5s
// [1, 0] after 1s
// [1, 1] after 1.5s
// [2, 1] after 2s