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You might be asked in the interview the question like this, what will be council locked here?

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And as you can see here, we have console.log full and then full equals one.

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And actually, this is a typical question regarding hoist him.

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So what hoist an error means?

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It means that the declaration of your variable will bubble to the top of the file.

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And this is how it works in JavaScript when you're using a VAR keyword or function keyword.

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So the question is what we will see here we have here counsel look for and foo is a variable, but as

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you can see, it is not declared.

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And then the second line we have foo equals one.

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Actually, we will get here and there.

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Let's check the sound and reloading the page and we're getting foo is not defined by it is happening

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because, yes, the first line which is executed is console.log and food is not defined inside of a

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file.

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This is why we have this error.

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So the correct answer here will get an error because Foo is not define it.

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The main problem is here that typically you will get the answers just to answer on the paper without

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any usage of computer, because obviously programmers are not using computers every day.

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This is where you can't really tested in browser, and you need to understand how all this stuff is

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working beforehand.

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After a correct answer, you probably will ask something like this.

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So the next question then will be OK, where console.log in here for?

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But after this, we have our full equals tool.

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And actually, here are the huge difference, because the first question we had here who equals one.

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But we didn't have a creation of the variable.

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But here we have our tool, which is actually a creation of the variable.

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But you might think, OK, what happens after console.log, which means we will still get an error that

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does not define it because of what happens later.

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But actually, this is a wrong answer, because the main idea is that while declaration is bubbling

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to the top of the file, which means it is exactly the same Cold Lake right in here WAFU.

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And here were just a sign.

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In footnote, all this is exactly the same code.

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This is how JavaScript interprets this code.

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This is why, if we will open the browser, you can see that we get an undefined it.

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Why it is happening because actually, here we have our full.

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And in this case, WAFU is undefined because we didn't assign any value.

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After this, we have a console.log for where we get an undefined, and only after this were sign in

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to inciteful, which means it won't be an error.

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It won't be, too.

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It will be undefined.

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And this process is called hoisting.

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If you answered correctly, you might get one more question regarding hoisting.

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As you can see here, just question three we have here four equals three, then console.log four and

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then VAR full.

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And I think now you know the answer.

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Yes, we have here were four and it bubbles to the top of the file, which means actually this who is

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exactly like its in here, which means on the first line were defined in full property on the next line

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were sign in foot or three.

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And after this were console.log and full, which means it will be equal.

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Three.

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And it doesn't really matter that waffle is going at the end, it will be bubble to the top.

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Let's check this out.

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I'm reloading the page and we're getting three.

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And this is exactly what we were waiting.

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And you can get exactly the same question, but not with one, but with function keyword.

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If you have somewhere in your called function and then the name of your function and then inside you,

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right?

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In some logic, the specific definition will bubble to the top, which actually means it doesn't really

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matter in what line of your code you are right and function for.

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It will be the first line that will be executed in JavaScript, which actually means if here before

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I will call for, it is totally fine.

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As you can see in browser, we're not getting any errors because this full function is bubble to the

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top and it works exactly the same.

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Like, Wow!

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And here is one more important thing that you must add to your answer.

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You must mention that we can use Konst and let.

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And we don't have any problems with them because both const and let are not wobbling at all.

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Which means if we're right here, const equals one, it won't bubble anywhere.

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If it is defined on the 17th line, then it will be existed on the internet and flame, which means

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we don't have any problems with constant LED.

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And the way the JavaScript interprets our code is exactly the same code that we're seeing on the screen.

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So you can just say that you're using const and let in every single project and you don't have any problem

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was bubbling of the variable or was hoisting.