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You might get a question check that user with such name exists in the real object.

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Obviously, it can be not name or not user.

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But the idea is that you need to check a property of the object inside an array.

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And actually, there are different ways to implement this.

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And the worst way possible is by using for Loop, because as I said previously, full loop is super

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low level and it is not as a tool for this specific task.

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So let's look how it looks like this for a loop.

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So here we want to create the function, for example, is name exists.

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And here we must pass two arguments.

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First of all, it's a name.

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And secondly, it is a ray of our users know inside of a must create a property which will be Boolean,

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and it will show us that we have this user inside an array.

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So here we can make a let exist, and by default, it will be false.

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Now we must try to follow up.

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So here we have our left eye from zero and I less than user's length.

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And here we make an A-plus plus.

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Now what we want to do inside for every single element, we must check its name.

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This is why here we are checking the user's I don't name equals our name.

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And if it equals, then we want to assign inside to exist through after a for loop.

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We want to return our exist property.

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So yes, of this code will work.

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Let's check this out.

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But it is super low level.

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As you can see, we have, for example, named John.

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Let's right here, John and here comma our users, as you can see, widget and true because we have

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such user with such name insiders, Ray, if I am right in here, just full, where get and false.

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But the problem with this code, it won't show that you're an advanced developer.

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This is why I want to show you three other possibilities to ride this code.

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And actually, all these three possibilities are OK.

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My favorite will be a single line here so we can create a function is name exists.

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And here we get a name and the right.

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And as you can see here, I didn't write user's battery because now we can use this function on any

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data and know what they want to call.

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Here is a red dot sum.

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And if you don't know what Sam is doing, you can call some on the ray and given side some predicates

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so you want to check something inside.

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In our case, Sam will return as true if we have at least one single element which fulfills our condition.

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So inside Sam, we can write element and we want to check here element name equals our names that were

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passed inside.

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And this is literally the same code lake result here, but much smaller.

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Let's check the sound I religion page and I'm just type in his name exist as you can see where getting

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through.

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So actually, Sam is the best solution to this question, but it is also possible to use other solutions.

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So let's command the sound and try again.

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We have here again two arguments name and array.

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Now inside we can try and find element with such name.

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This is why here let's create an element and we're using here a red dot.

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Find we're getting our element.

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And here we want to check element dog name equals zone name from the top.

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But in this case, our element is actually an object.

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It's not a Boolean.

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This is where here must wrap our element in Boolean to return Boolean and not an object.

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In this case, it will work correctly.

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I'm reloading the page.

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As you can see, it is working exactly like this.

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So the main difference is that we must try it a little bit more code because we must convert it to Boolean.

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And the last thing that we can use here is actually not find but find the index.

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And if you don't know what, find the index is doing is exactly the same logic, but were found in the

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index of this element.

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So if we can find the object with search name inside our array.

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So here we're not getting our element button index.

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And after this, we know that if this index is less than zero, then this item was not found.

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So here we can try to return index bigger than zero.

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In this case, even though, OK, it is bigger than zero.

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We have this element inside the rape, and as you can see, this code is working exactly the same.

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So my approach would be SAM.

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The next approach will be find index find is also OK, but you should not use for loop because it is

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highly inefficient for such a task.