Arrays in JavaScript are a special type of object. They resemble Python Lists (an ordered and changeable collection, allowing duplicate members and members of different types).
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You can use the bracket notation to access and modify the array elements.
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You can create an empty array and then add values to it:
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Array constructor syntax
You can make an empty array using array constructor syntax:
const numbers = new Array ();
But it is more common to use the array literal syntax instead:
const numbers = [];
Madness : In an array, you can leave some elements undefined!
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Note how the trailing comma does not denote an undefined element!
Allowing undefined elements leads to more annoying behaviors.
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length is calculated as one more than the highest index!
And the craziest thing is that you can overwrite the length property!
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Convenient syntax for fetching multiple elements:
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You can even do this:
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Use arrays of arrays for multi-dimensional arrays:
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Array object comes with many useful built-in operations. We will explore some of these in future lectures. For the impatient, please visit Array on MDN web docs