IntervalCancellation.js

// Given a function fn, an array of arguments args, and an interval time t, return a cancel function cancelFn.

// After a delay of cancelTimeMs, the returned cancel function cancelFn will be invoked.

// setTimeout(cancelFn, cancelTimeMs)
// The function fn should be called with args immediately and then called again every t milliseconds until cancelFn is called at cancelTimeMs ms.

var cancellable = function (fn, args, t) {
    fn(...args)
    intervalId = setInterval(() => {
        fn(...args)
    }, t)
    cancelFn = () => {
        clearInterval(intervalId)
    }
    return cancelFn
}