有哪位大佬，帮忙看看为啥打印的是undefined， 1， 1 而不是 undefined， 1，undefined

const debounce1 = (func, delay) => { let timeout return () => { console.log(timeout, '--timeout--'); if (timeout) { clearTimeout(timeout) } else { timeout = setTimeout(function () { func(timeout) }, delay) } } }

const log = debounce1((timeout) => { console.log(timeout) }, 5000) log() log() log()

结果 // undefined '--timeout--' // 1 '--timeout--' // 1 '--timeout--'