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The scope of a variable can be at the level of a class or a function.

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So far, you learned about classes and functions, the class contains all of your code and each function

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contains a small grouping of your code.

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When you make a variable, it can exist at the level of a class or at the level of a function.

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So in this lesson, you're going to learn about function, scope and scope.

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First thing you'll need to do is create a new class by yourself inside the section for a project, create

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a new file name scoped out Java, and make sure the class has a main method.

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The scope of a function spans the two curly brackets, a variable inside the function can only exist

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in the function scope.

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When this line of code runs, Java creates the variable and when the function ends, that variable falls

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out of scope, it ceases to exist outside of the function scope.

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It's gone.

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And so inside, man, I'm going to make it into a variable named Appel's.

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And now I'm going to make a function called some function, this function is void.

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It's not going to return anything.

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And it will take no parameters.

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Now I'm going to call some function from within men.

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And inside some function, I'm going to try to print the apples variable that I declared inside men.

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Running my code.

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And obviously, it doesn't compile, you cannot access a variable from outside of its scope, you created

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the variable inside main, the variable only exists inside the main scope.

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So if you look at the image, I highlighted the scope for you.

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It starts at the first curly brace and it ends at the second curly brace.

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And you cannot access the variable from outside of the scope where you created it.

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Instead, we need to write the variable inside some function.

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Now we can recompile and run the code.

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And it prince 5:00, no surprise there.

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And now try printing the variable for Min.

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And the code doesn't compile, as I just said, you cannot access a variable beyond the scope of its

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existence, this variable only exists at the scope of some function, and you cannot access it from

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the scope of another function.

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Now, a variable in a class exists inside the class scope and the scope of a class spends all of its

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code.

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If you think of scope as going from the first curly bracket to the second curly bracket, it makes sense

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that any variable that you declare at the scope of the class is available anywhere inside the class.

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In this case, I declare the variable dogs at the level of the class and have a look.

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I can access and print it from anywhere inside the class.

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OK, now remove the code from earlier.

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But leave the some function call, and now we're going to make it a variable dogs at the level of the

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class and set it equal to five.

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Now, the scope of dogs spans the entire class, so we're going to print it from the main function.

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As well as from some function and the only reason we're still getting an error is because we have to

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declare the variable a static, since we're calling it from static methods.

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Again, don't worry about what static is for now, we're going to dive deeper into it in module two,

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just know that every variable and every function at the class level needs to be static.

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OK, rewriting our code.

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And it prints five on both occasions, the scope of dogs is at the class level, which means we can

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access it from anywhere inside the class.

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In this lesson, you learned about function, scope and scope, when you make a variable inside a function,

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it only exists within the function scope.

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And when you make a verbal at the level of the class, you can access it from anywhere inside the class.