Console.log（）打印Q中的Promise对象的状态和值

Question

When I try print a promise object from Q, I got the following result.

var Q = require('q');
var defaultPromise = new Q();
console.log('defaultPromise', defaultPromise);

defaultPromise { state: 'fulfilled', value: undefined }

Where do the field state, and value come from, I try to find them through visual studio code, the fields are not there.

Answer 1

A promise must be in one of three states: pending, fulfilled, or rejected.

A promise must provide a then method to access its current or eventual value or reason.

Promises/A+

Q(value) returns a promise that is fulfilled with value. In your case, undefined. Q API Reference