Promise Test - Qiita

function sampleResolve(value) { return new Promise(resolve => { setTimeout(() => { resolve(value); }, 1000); }) } function sample() { let result = 0; return sampleResolve(5) .then(val => { console.log(result, val) result += val; return sampleResolve(10); }) .then(val => { console.log(result, val) result *= val; return sampleResolve(20); }) .then(val => { console.log(result, val) result += val; ret