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All right.

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So it's time for another quick set of exercises.

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This time we're going to cover javascript objects.

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Just the basics.

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You know the drill by now.

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I'm going to give you some code and ask you to evaluate it without just copying it into the console

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.

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So here's the first one we are declaring an object and then we're adding four different properties to

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that object.

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And I want you to figure out which of these are valid code and which will cause problems.

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So go ahead post a video and give it a shot.

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OK so let's discuss the answer here.

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If we go ahead and create a new object some object equals empty object the first thing that we're doing

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is trying to add in Hedwig under the key underscore name.

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So does it work to do that.

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The answer is yes.

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If I look at some object you'll see that we have Headrick stored under underscore name.

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It's a little bit unorthodox to see that but it's definitely OK.

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So the next one here this is also valid some object dot age you can see get some object it has underscored

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name Hedwig.

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Age 6.

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Next up we're using a variable called Propp which is equal to the string color.

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And then we're using Propp as the key inside of square brackets and setting the value to be read.

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So if we copy this over and we look at some object you'll see that we get color Colan red which is valid

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.

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Lastly some objects dot one two three.

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Setting that to be true that's problematic.

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We can't use the dot notation if we have a property starting with a number.

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So that's the only one that's an issue.

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Although again using underscore is not a great idea but it doesn't cause a problem.

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So here's the second exercise.

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Have a large nested object and I want you to write code to retrieve the string Malfoy right here from

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some object.

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And remember to go one layer at a time.

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So go ahead post the video and try and write the code to retrieve Malfoy.

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OK so the answer here is that we first need to access the friends array and to do that it's some object

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friends and then we need to access the first object instead of the friends array which is right here

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.

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And then we need to access the name property out of that array.

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So let's type that solution.

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I'm going to just copy some object over and we're going to need to start by accessing the friends array

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.

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So Dot friends or we could use square brackets.

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That gives us an array with three different people each one with a name.

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We want the first one.

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So some object friends bracket zero.

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That gives us an object with name equal to Malfoy.

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And then we want dot name.

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And again we could use square brackets as well.

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So that's all we need to do there.

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The key to answering these is to go one step at a time burrow down or drill down to friends and then

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to the first object and then get name.

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All right so that's it for this quick set of exercises.