Async/Await

gistfile1.txt

function sleep(ms){

    return new Promise(function(resolve){
        setTimeout(function(){
            resolve('sleep for '+ ms + 'ms');
        }, ms);
    });
}

async function asyncFunction(){

    console.time('asyncFunction total executing');

    const sleep1 = await sleep(2000);
    console.log('sleep 1:' + sleep1);

    const[sleep2, sleep3, sleep4] = await Promise.all([sleep(2000), sleep(1000), sleep(1500)]);

    console.log('sleep 2:' + sleep2);
    console.log('sleep 3:' + sleep3);
    console.log('sleep 4:' + sleep4);

    const sleepRace = await Promise.race([sleep(3000), sleep(1000), sleep(500)]);
    console.log('sleep race:  ' + sleepRace);
    console.timeEnd('asyncFunction total executing:');

    return 'asyncFunction done';
}

asyncFunction().then(data=>{
    console.log(data);
}).catch(error=>{
    console.log(error);
});

console.log('after asyncFunction code executing....');