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In the previous video, we talked about the structure in this video.

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Let's focus on risk parameters.

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Risk parameters are a way to pass an arbitrary number of elements to a function, which means that we

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can pass an indeterminate element to a function if this particular definition is not clear to you.

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Let's demonstrate something here.

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Let's say that we have this particular institution.

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And this institution.

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It takes, let's say, 20 applicants.

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So after 20 applicants, this particular school cannot accept any incoming application.

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And let's say that we have, let's say, 40 or more students left.

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Good.

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But with rest parameters.

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What is saying is that.

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Okay.

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Well, we are saying that we are taking 20 applicants.

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But any applicant who applies, we will still what accommodates you into the school.

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So if we take this in code, we can say that the school is a function.

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And then the applicants are called the agreement.

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So inside this coup, it hosted all the applicants.

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So this applicants are called the agreement.

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So with the rest parameter.

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We have access to the parameters we are requesting and any additional parameters being passed into the

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function.

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So let's get back to the slide and let's take this one to as an example, let's say that this is also

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a function, right?

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So this function, let's say it takes, let's say five or ten users, but after it has finished taking

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the required users, we still have some users which has left.

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So with rest parameters, we can still pass this user into the function and the function can have access

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to the rest users.

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So as the name implies rest, it takes the rest of the argument and the method using the red dot.

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So let's get back to visual ID code and demonstrate that.

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Well, so here let me comment and call this one as risks parameters.

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To better understand risk parameters, we need to understand what is called engagement.

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So let me demonstrate that one for you to see.

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Let's say we have a function that adds two numbers.

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To see two numbers, and this one would take in A and B.

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So inside this function, I have access to what is called the argument.

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So if I call the function the at two numbers and let's see the equipment that we have inside the function.

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Let me enlarge it.

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If we see that this looks like an array because we have the square bracket here and the close in here

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is that.

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But it's not an array where the argument object is not a real array while rest parameters are an array.

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So I'll show you very soon.

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So take note that the argument is not real array.

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So anything that we pass to this function will be available inside the argument.

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So let's pass in here.

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Let's say 20 here.

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If I save it, we see that it has added inside my argument and let's say I want at ten we see that it's

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been added inside my argument.

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Okay, so anything that you pass into the function as an argument would be available inside this argument

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property.

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That's one thing to bear in mind.

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Again, this is not rare array, meaning we cannot use some of the methods on this particular argument.

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So now you know what argument is.

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It holds all the arguments we pass to this particular function.

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Now let's talk about rest.

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So now inside this function, how can we make use of res to rest is like an improvement on the argument.

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Okay, before I show you the rest, let's try to loop through this particular argument here.

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VERRASTRO We can still have some methods, but ideally is not real every so we never use that one by

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using some method on that.

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That is why rest comes into play.

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So let's say let me remove this from here.

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And for rest parameters we bring in dot, dot, dot and then any variable we can make it.

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So let's say the arguments, the ag or the arguments or rest.

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Is that so?

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If I console.log.

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Rest.

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Now you could see that this is perfect array.

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So it means that we can have access to any variable that we pass into this function and to pack them

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or put them inside an array like that.

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That is good, right?

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So with this one, I can add as many arguments with this particular function I can pass in, let's say

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even me a string and then to be added into the array.

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And this is crucial.

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Let's say that this particular function takes in two arguments.

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Now we have a function with rest parameter.

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What about a function with argument and with rest parameter?

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Before I would demonstrate to you the logic behind this function.

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Let's go ahead and create a function that would take in our own arguments and then rest with rest parameter.

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So now let me copy this one and comment this one out and come down here.

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Now here we can pass it A and B like that.

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Now we know this one holds the.

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So here I can have access to my A and then B and I have two and 20.

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You can see that it couldn't print out the three and me because according to this implementation, it

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says that this function needs two arguments.

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So we take in 20 and ten, as we see here.

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But to have access to extra argument we pass in, we have access to it by making of comma and dots the

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ax.

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The argument or risk it can be anything race or the and so most times make use of race or the arguments.

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So now I have this.

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So if I console.log the rest.

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Let's see.

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The difference is if I console.log.

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The rest.

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Now.

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It's wrists.

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Yes, you can see that.

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Now, we have two things happening here.

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We have the original agreement, which is 220 and ten as that.

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But for the rest, it has taken the rest of agreements and then put them inside an array that is key

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nutrient bearing in mind the rest agreements, take the rest of agreements and put them inside an array.

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And remember, one function can take in only one rest parameter.

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I'm thinking, what about a can I add?

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Let's say another rest.

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Let's say dot, dot, dot.

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Let's say raise to.

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Now see that?

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Got an arrow.

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So a function takes in only one race parameter.

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Let's create a simple function that would take in some arguments and find which one is the maximum.

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So the function would go like this find max or the maximum.

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And this function, let's say I want to find three numbers.

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Let's say A, B and C as a C note, three, C as that.

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And now I'm going to use map.

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Moth dart.

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Maximum.

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Then I'll pass in A, B and C, so let me console.log this one and let's see, just console.log it.

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Okay.

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So now if I call the function called find max maximum.

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Now pass in, let's say ten, 20 and 30.

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Which one is the highest?

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So if I save it, I get 30 because 30 is the highest among this.

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So what about if I add, let's say 100 into it number?

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So I still see 30 because it didn't take this one into consideration.

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So to have access to this one, I'm going to use the rest parameter.

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Remember, the rest parameter will take the individual record and put it inside an array.

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So it is I'm going to be so inside my argument here.

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Instead of using some static arguments here, I'm going to use the dots.

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Let's see the rest of the numbers.

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And inside here, I'm going to use the same syntax as dot, dot, dot risk, meaning I'm taking the

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argument from here and passing to this particular method or function if I save it by list.

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Now see that I get 102.

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So let's see.

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I want to add let's say 200 and let's see, I could see that now we have it as 200 because now because

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of risk, it is taking all the agreement you pass in and then pass into this maximum function.

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That is how race works.