unleash/src/lib/timer.ts

const NS_TO_S = 1e9;

// seconds takes a tuple of [seconds, nanoseconds]
// and returns the time in seconds
const seconds: (diff: [number, number]) => number = diff =>
    diff[0] + diff[1] / NS_TO_S;

const newTimer: () => () => number = () => {
    const now = process.hrtime();
    return () => seconds(process.hrtime(now));
};

const timer = {
    seconds,
    new: newTimer,
};

export default timer;

module.exports = {
    seconds,
    new: newTimer,
};