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Welcome back.

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Let's continue on the implementation of a promise.

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So in this video, we are going to talk about a concept called resolving.

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You're going to hear this name a lot.

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Resolving simply means that getting the response from a function, meaning that resolving it can be

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error or success, meaning gets what is coming back from a promise.

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So how can we make this of resolving?

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Well, remember this entire function here.

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The value would be assigned into promise.

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So let's try to console.log promise and let's see what we have inside the promise that we have created.

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So if I check it, you will see that I have fulfilled and then undefined.

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Perfect.

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So let's go ahead and then I mean, read more code to get an actual value because what we want is these

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values.

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That is my user.

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Okay, not this.

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I mean, for what you see here.

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Okay, so how are we going to do it?

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So now let's remove this one again.

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This name can be anything perfect.

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It can be my promise or user promise.

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But think because this promise is fetching user, we can make it as user promise to be more specific.

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User promise.

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Perfect.

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So now I have my user promise here.

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So how can I get what I want?

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So here we go on the promise.

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We have two method core then and catch well we use then to get a value when a promise is resolved.

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So here I'll make use of dot then as a function call.

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So the then is used or is a function that gets a value from resolve here.

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So remember the then also takes in one argument that is callback so here pass in a callback function.

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It can be a function or a normal function.

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Let me use normal function here this time around.

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And here we go.

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Perfect.

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And again inside the callback of Dot.

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Then for this callback I'm going to pass in one argument and I'll show you in just a second.

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So inside the body here, how can we get the values for the resolve?

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So let me say that dot, dot, then dot then is as a function is used to get the value from resolve

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function in my premise in the resolve resolve function from promise.

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Yes.

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So here, one cool thing about resolve is that we can now pass anything that we want the user to see.

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So let's say that for the meantime, let's pass in.

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Yes, it is resolved.

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Good.

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So coming down here, if I serve this function, check my console, nothing being displayed.

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I can go ahead and say just display anything.

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Let's say that any value here.

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So when I save it, it will see that I have any value.

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But what we want is the response coming back from my promise.

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That is the result.

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So it means that anything we pass in as an argument to resolve, we can get it inside our callback function

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by providing an argument to the callback function of those.

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Then so here it can be anything, it can be data, it can be value.

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The choice is yours.

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So here this value now represents what is inside my resolve function here.

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So instead of this one, I cannot console.log the value or response from my result.

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Let's say that value from resolve maybe to be more specific here.

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Resolved.

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So here I cannot console the value and let's see if indeed we have it.

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And now yes, it is resolved.

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This test or response is coming from this function down here.

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Sorry.

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Up here.

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So instead of just returning this test, we won't get the user.

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So I cannot pass this user to my resolve as user.

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So if I save it, what are you going to see in a console?

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You are going to see what the user object because what we pass in to this function.

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So here we have this user inside my callback, then I just console.log down here a let's check it out.

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So when I say it nine you see that I have my user object.

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The function is resolved because there is all function is being called but not this.

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And again, because this condition is true, that is why this function is being called.

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But let's change this one to force when I save it.

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What's going to happen?

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Is this function going to be called or this one?

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Think about it perfect because it's force.

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This condition is false.

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Therefore this one will be called.

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So when I save it.

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Now, check it out.

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You see, we have beautiful error called on cuts in promise.

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This is the kind of error we are going to see.

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A lot, a lot, a lot.

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Okay, so this error simply means that we are making of promise, but we are not handling the error

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case in case the promise reject or failed.

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How are we going to display or get the actual error and send to the user because we are not handling

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that error here.

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That's why JavaScript by default gives us this error in time you see in promise.

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It means that there is something going wrong in your code that is the rejected or your premise is being

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failed.

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But we are not catching it or using it.

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So how are you going to make use of this reject and display?

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A beautiful error says that error fetching user or network error.

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All right.

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So let's get into that in the next video guide.