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So to finish up here I have a quick little quiz.

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I'm just going to paste in some code and I'd like you to evaluate mentally without typing this up what

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you think this returns.

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So we define the function and then recalling it at the end.

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So what's returned from do math

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.

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So the answer here is true.

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So let's step through how that works.

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Very first thing we're declaring numb to be 8.

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Then we have a function do math but that doesn't run yet.

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So the next thing that runs is numb plus equals 1.

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So number is now 9.

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So this is the same as this one appear because they're in the same scope then we're calling and do math

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.

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So instead of do math we're writing numb plus equals 1.

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SO NUMB was nine.

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This is referring to the same number.

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So it's now 10.

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So all this does here is check if numb is evenly divisible by five.

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So 10 is divisible by five.

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So we return true and that's it.

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So as I mentioned scope is notoriously tricky to explain.

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It's something that we've only scratched the surface of here but we covered the important parts which

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is that anytime you define a new function it gets its own new scope and it can access variables that

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were defined outside the function but inside a function if we defined something it's not accessible

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outside the function.

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So there's one more quick example I want to highlight which is if I have two functions one called the

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high end inside of hi I'm just going to declare a variable name equals Rusti and then I'm going to cost

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about Lague name

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and then I'm going to have another function called by and I'm not going to define Rustie there but I

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am going to Conchobar blog name if I run high and I execute it.

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I of course get rusty because I defined a variable name is Rusty instead of high.

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And then I printed it.

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If I do this with by However I get undefined

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and that's happening because name is not accessible in the scope of this by function.

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So this goes to show that every function has its own scope and they're not shared between functions

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.