create your own Promise

Question

Promise is widely used nowadays, hard to think how we handled Callback Hell in the old times.

Can you implement a MyPromise Class by yourself?

At least it should match following requirements

1. new promise: new MyPromise((resolve, reject) => {})
2. chaining : MyPromise.prototype.then() then handlers should be called asynchronously
3. rejection handler: MyPromise.prototype.catch()
4. static methods: MyPromise.resolve(), MyPromise.reject().

This is a challenging problem. Recommend you read about Promise thoroughly first.

Code

class MyPromise {
  constructor(executor) {
    // your code here
  }
  
  then(onFulfilled, onRejected) {
    // your code here
  }
  
  catch(onRejected) {
    // your code here
  }
  
  static resolve(value) {
    // your code here
  }
  
  static reject(value) {
    // your code here
  }
}

Source

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