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Hey there.

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Welcome back.

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In this lecture we're going to be taking a quick look at what an enum or enumerated type is.

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An enum is simply a data type that consists of a set of constant values.

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These constants are used in conjunction with other APIs to define presets for specific things.

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In other words, an enum is simply a container of constant values with meaningful names to make it easier

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for us to code.

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Imagine if we wanted to have a set of ten possible player states for a player in our game, and yet

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we never defined a constant value to represent each one of those ten player states.

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That would be a total mess.

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However, we could have an enum to represent the state of a player when they're walking or jumping or

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falling over.

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However, if we didn't have that enum, we would have no idea what value to set on a player.

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To give us that particular state, we first have to define that constant value to give us that state,

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and then we can bundle all those values together, give them each meaningful names like jumping or falling

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over, and bam, you've got yourself an enum.

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I'm going to create a script real quick and server script service to demonstrate what an enum is, and

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you should know to access all of the enums in the Roblox API, you just type out the keyword of enum,

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and then you can index it.

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And here it will show you all of the different enums that exist in the game.

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And these enums are used for many different things, and they help us interact with the many services

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and API functions that we have in the Roblox API.

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For example, one of these enums is called a part type.

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And if we index the part type enum here, it shows us a set of constants that we can go ahead and apply

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to a part in our game to change its shape.

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So let's go ahead and demonstrate that I'm going to create a new part.

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And I'm going to position my part above the origin in the workspace.

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So that'll be equal to vector three dot new.

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And we'll just put it ten studs above the origin point.

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We'll make sure this part is anchored.

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And then I'm going to set its parent equal to the workspace.

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And when we set it into the workspace you'll see it's just a regular part or a block.

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But then I'm going to yield here for five seconds.

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And then I'm going to update the shape property.

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And here it tells us it takes an enum of part type.

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And we can go ahead and change the shape of our part.

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For example we could change it to the part type of ball.

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And then I'm going to wait for another five seconds.

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And then we can change the shape maybe to an enum part type of let's say cylinder.

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We can wait another five seconds and then we can change the shape maybe to an enum part type of let's

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say wedge.

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Each of these represents a constant value, and these are just the names that Roblox has given to them.

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So one value, they've called it ball, which will set the shape of the part equal to ball.

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Another one they called it cylinder which will set the shape equal to a cylinder, and so on.

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So an enum is simply just a set of constant values with meaningful names.

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So if we go and run our game here.

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As you can see here is our regular brick and then it should change into a sphere.

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There you go.

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There's our little sphere right there.

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And then it should change into a cylinder.

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There's our cylinder and then it should change into a wedge.

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Perfect.

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There we go.

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Here is our wedge.

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Earlier I mentioned talking about having an enum for the different states a player could be in, and

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that actually exists within the Roblox API specifically for the humanoid instance.

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So every player's character in the game is going to have a humanoid, and I'm just going to create one

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here real quick.

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I'll create a new humanoid, and these humanoids have a function inside of them where we are able to

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change the state of the humanoid, and it takes an enum of humanoid state type.

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So if we access the humanoid state type enum and we index it here, it shows us all the different constants

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or possible values that a humanoid could be in.

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For example, they could be in a dead state, they could be in a state where they're falling down or

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they're jumping.

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Maybe they're running or they're seated.

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They could be in a state of free falling or they're swimming, stuff like that.

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So there's a whole bunch of different constants here to define the different states that a humanoid

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could be in.

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We also have another enum when it relates to user input for example, how do we know what particular

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key a player is pressing on their keyboard?

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Well, thankfully we have an enum called Keycode, which stores all of the different keys that a player

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could possibly press on their keyboard.

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So that way when a player does press a keyboard, it'll tell us what enum Keycode it was, and then

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we can go ahead and compare that key code to another key code.

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And then if it matches, then we can execute some functionality based on what key a player presses on

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their keyboard.

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We also have another enum for storing specific fonts in our game.

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So this is called font.

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And here are a bunch of different fonts that we can set for stuff in our game.

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We also have an enum for font sizes.

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So if we access that there, boom!

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We have a whole bunch of standardized font sizes where if we have different font styles, different

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font weights, there is just a whole bunch of different enums in the Roblox API.

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So as I stated, an enum is just a set of standardized values to enable us to communicate between the

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different functions and services in our game.

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If no enums existed, we would have no idea what values to set in properties or passed to functions

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to get the state we want.

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That's all I have for you in this lecture.

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Enums are quite simple and I'll see you in the next one.