How was nextValue assigned a number?

Question

I have two questions: 1- When I run my code in the workspace, nothing comes out. Here is my code:

var calculationPromise = new Promise (function (resolve, reject) {
  setTimeout(function(){
     resolve (1 + 1);
  }, 1000);
});

calculationPromise.then(function (value) {
 return value + 2;
}).then(function (nextValue) {
 console.log("The final value is", nextValue);
});

2- When I watched the video, I didn't understand how nextValue was assigned with the result number 4.

Answer 1 · 2018-05-25T17:48:09Z

May 25, 2018 5:48pm

Hey Moe,

So, your code works in the console. Did you have your console opens when you ran your code? It worked fine when I tried it out.

NextValue is just the name we give to the parameter that function is receiving. The important thing about promises is that we are requesting that the functions be done in order (asynchronously) rather than all at the same time (synchronously.) We are waiting for one thing to finish before we do the next thing.

That means in this case we start with a var calculation Promise = 1+1 (which is 2, of course,)

Then we pass that number as the new parameter to calculationPromise.then and we return that value +2 (so that's now 4)

Then we pass that number along again to the second .then as the new parameter (nextValue) which interpolates it into our console.log sentence. Here we could call the parameters anything we like as long as we are consistent.

Does that make sense?

Answer 2 · 2018-09-01T00:26:14Z

September 1, 2018 12:26am

How does the anonymous function in the promise constructor return a value when it doesn't explicitly return anything?

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Moe Ghashim

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How was nextValue assigned a number?

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Amber Clark

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