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There also is a useful method for adding elements to an array and returning a brand new array which

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again can be useful in situations where you want to create a copy of an array,

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maybe after adding new elements to it, let me show what I mean.

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I'll comment this out and instead create stored results here by using my test results

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and now here, there is the concat method which we can call. The concat method allows you to concatenate,

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so to add elements at the end of an array.

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Now therefore it's of course a bit like push, with push you can also add items to an array, by the way also

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more than one item,

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they will be added at the end but concat actually here takes an array or multiple arrays but not individual

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numbers or items in general but arrays, one or more arrays and combines these arrays with this array.

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So it does not add these arrays as new nested arrays,

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that is what would happen if you pushed an array, that would add this as a single element in the existing

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array hence creating a nested array, concat on the other hand will pull out all elements of the array

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you are passing here and add them as new elements to the existing array and it will then also return a brand

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new array. So it will create a copy of the array,

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add these items and return that copied brand new array, hence creating a new place in memory and a

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new address.

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So here for example, if we have 3.99 and 2 and I concatenate this here, what you'll see is if

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I reload, here we get the array with 3.99 and 2 at the end which are the two values I just added.

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And of course please also note that when I push 5.91 to test results,

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this does not end up in my stored result which is the first array I output here because concat returned

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a brand new array. So you see no 5.91 here in the first array, only in the second one.

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So that's also useful, concat can be really useful if you have array data and you want to combine it

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with an existing array and the fact that you get a brand new array is also quite convenient because

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that often avoids problems where you manipulate an existing array when you actually didn't want to

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do that.