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What's up, everyone?

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Today, we're going to learn about variable type coercion and mediation.

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So these are very important aspects of JavaScript language basics right now, what coercion and mutation

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means.

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Sorry about this.

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I'm just going to wait here to open this one now.

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What I'm going to do is actually we are going to put it here and say variable type coercion and mutation.

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Very good.

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Now you hit it, right?

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No.

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That's it.

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Now we're going to do we do have the first name and I'm not going to comment on this one, but we can

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comment on all of this.

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So if I refresh, I'm not going to I'm going to be hello world from external file.

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That's one from here.

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And that's all good.

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I don't have to be worried about that.

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So you can comment the section of the code like this.

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And that is what also comments are therefore.

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So not just to make a comment about what you what your coat will be about.

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And also sometimes you need to comment on things in order to continue working on something else.

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Nice.

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So what is type coersion?

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So we have the first name, we have the last name.

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And what we can do here is we can just put those together like in one.

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I'm not I'm just going to say Konz a lot.

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Guns a lot, and I am going to join the EU first name, so how we can join the things, we can join

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the things with the plus symbols.

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So this is not addition here.

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Underscore last night.

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Right.

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So if I do it like this, so this is not going to be a first name plus last name, it will be joined

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actually.

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I will have Peter Collins.

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Now, what about this very type conversion, what we can do after the plus symbol?

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What I would always do, I will leave a space like that and I will need to concatenate again with the

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plus symbol.

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So it will be first name space last night.

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So they're all they're old now.

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Transfer or let's say not transferred is not good work.

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So they're all now considered as a sphinx because first time hold strings.

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This one is considered a space of the string and this one is a string.

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Now, we do have these old.

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So what we can do, we can just create additional work here and C plus old.

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So Peter Collins is.

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Speace plus, so we need to congratulate again.

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So now I would like to see Peter Cullen is 33 years and we can just again attach or concatenate something

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else years old like this.

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Let's check it out now.

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So Peter Collins is 33 years old.

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So what I did have I have a mixed type of variables.

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One, it's holding a number like thirty three, which hold integer number, the other one that hold

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string.

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So that is how we can join this together.

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That is how it's called type Hershon.

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Now, one more thing before we go so we can be clear.

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So remember, we declare one by one here variables we can declare.

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In one line, certain variables, first, variable, second, third and fourth right now.

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So I have this right here, so third, fourth, so I save it and now if I try to access some of them

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comes a lot.

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For example, first, not that one.

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So I will have undefined value because actually we just declared it.

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Now we can define them in the lines below or assign a value

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in the lines below.

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So what can do?

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You can say first here, I don't have to put water in order to specify if it's variable.

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I can say first I'm going to say Rick.

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Sammy Gall here, and I'm just going to copy this one couple of more times, so first and the second

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it will be Andy.

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And third,

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third will be John.

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And fourth, Melissa.

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So now if I get space, if I can, I can I mean, I can show them here.

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If I do lock first, it will give me not any more undefined.

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It will give me a ring.

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Also, if you want to do so, I'm going to say, plus your karma and I'm going to see here, OK, second,

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and that will give me first week and the second with commas in between.

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So that is how we can just declare multiple variables in one line and after that in our code below,

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we can just assign of values to them.

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That's very good, right?

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What else we can do here is we can mutate because the actual was very type coercion and notation.

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Now this is and the first and first is and second is Andy.

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But what if I change my mind and just want to put a second as a second place?

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I just want to put it.

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I don't know.

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I don't know.

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Novac.

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So you should know who's Novak?

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Is Novak Djokovic the famous tennis player?

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Right.

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So if I do it if I copy it right now, he and I should see Rick in Novak in a second place.

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Right.

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This is called variable mutation.

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So we mutate its value.

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Right.

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Because here was and now the second place, it's Novak.

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But because we are printing press here, that's why he's grabbing this value, the initial value from

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Andy.

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Now, we do have different value, and that is why we are seeing Novak here.

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So how cool is this?

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We can just changed our values as we won in our code as we need them.

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Right.

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So that is called a signing, declaring a variable, assigning a valuable in mediating.

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This is called coersion.

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When we put different types of variables with different values inside in one single go into one single

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line.

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So JavaScript is more and knows and that's not the case with other languages that, OK, I'm going to

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put them, I'm going to just treat them all as a string's.

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That's all you need to know right now.

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And I hope you enjoyed this lecture.

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And it's we're still working with variables, but it is what it is.

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So we're learning a lot every day.

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Something new, every lecture, something new.

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So thank you very much.

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I hope to see you in the next one.

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And I hope you enjoyed this one.