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In this video we're going to start to clean up our set color function as I mentioned in the last video.

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There's definitely a little bit more appropriate syntax so we can use here to decide exactly what color

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we're trying to work on.

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So we could refactor this instead of having a series of IF statements we could instead use a switch

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statement that would look like this.

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I could instead say of instead the if statement right here I could say switch over color and then open

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up a curly brace and notice how I've still got the closing Curly race from our if statement we had just

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a moment ago right there.

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So then inside of here we could add in a case where color is equal to the string red.

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So if color is equal to red we can run this entire f statement right here so I'll tab that in like so

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and then for this to be a proper switch statement or a proper case.

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We always make sure we terminate the case with the return at the very end.

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So we don't fall through to any other case statements or in other cases that we might have inside of

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here so I'm going to say this really quickly and do another quick test just to make sure everything

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still works and yet it still looks good to me.

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Now even with this change having the nested IF statement here is still a little bit challenging to read.

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So there is yet another way that we could refactor this.

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This is a totally optional refactor but it definitely would increase the legibility of what's going

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on here.

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So I could say I could use something called a ternary expression a Turner expression is going to essentially

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check one statement and then if that statement evaluates to a truth you value it will run some immediate

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statement like in this case return.

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Otherwise it will run some other statement like set red.

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So essentially ternary is going to do exactly what we have with our if statement right here already.

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But it's just going to kind of condense down this logic so to do so I would write out red plus change

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greater than fifty five or read plus change less than zero.

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And here's where the ternary comes in we'll put in a question mark like so the question mark means that

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this is going to be the expression we want to run.

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If all this evaluates to a truth we value unfortunately we cannot return directly from a ternary statement.

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So instead we're just going to evaluate this expression to know like so that essentially means don't

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do anything.

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So if this is true right here if we are going to be outside outside of our bounds of red then don't

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do anything at all otherwise.

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So I'll put a call in there and that means if this is all SAE then do this.

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And in this case I want to update red by calling set red with red let's change now we can clean up that

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entire if statement.

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We're down to just one line of code.

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Now you can definitely argue that this is kind of hard to read right here especially if you're not familiar

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with ternary expressions.

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But once you start to get a little bit more familiar with them.

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Well you're going to be very comfortable kind of taking a glance at this and understanding what's going

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on.

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So I'm going to again save this.

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We'll do another quick test now if you see any error inside of your simulator right now.

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I can just guarantee you that you've got a typo somewhere inside of this line.

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So do double check this line of code double check the entire switch statement because if you're seeing

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an error that's only popping up right now.

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You definitely have a typo right here OK.

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So I'll do another quick test.

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I'll increase red Yep decrease red.

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Yep.

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Still works.

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Very good.

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Now we can easily essentially copy paste this statement right here and handle our other two colors of

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blue and green as well.

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So going to copy the case red paste it once and twice and I'm going to go through it and make sure I

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change all the color references inside of here.

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So first I'll update the string to be green all then do red red.

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Set red and red.

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So I have to do four more changes here.

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Make sure you do four changes on this line right here.

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My first one there's one there's two I'll do red right here inside of the parentheses.

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There's three.

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And then finally I will update set red to set Green.

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There's four.

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So make sure you do for updates as well.

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Now we can finish up with the last case.

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So I'll update.

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Case Red I'll change that string right there we want to handle a case of blue.

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Here and now I'll update this line again.

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Once again we'll have four separate changes.

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So here's one here is to here is three and there's four.

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I updated the setter as well so once again if you have an error at this point going forward chances

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are you made a typo somewhere inside of here.

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So I beg you please triple check please make sure that K screen has no mention of red whatsoever and

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make sure that case Blue has no mention of red whatsoever as well.

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The last thing we will do here.

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Technically we don't have to do this but usually by convention in a switch statement we add in kind

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of a default case at the very bottom.

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We say default like so.

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So if our color that we passed in did not match red green or blue we'll instead run this case right

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here.

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In which case we'll just return and say don't do anything okay.

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So now our set color function can handle all these different types of changes now that we've updated

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set color.

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We can go back down to all of our callbacks down here and we can update set blue and set Green to use

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set color instead so we'll start off with blue first.

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I'll change this to set color and set color again make sure you update both those then as a first argument

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will pass in blue as a string and as a second argument will pass in for the first one positive color

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increment and for the second one will do negative 1 times color increment all right.

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So once again make sure you've got set color set.

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Color blue and blue add strings and then positive color increment and negative color increment now will

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repeat that same process on set green.

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So we'll do a set color on both those string of green and then our second arguments will add in those

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commas and I'll do negative 1 times color increment and the first will be positive 1 All right and that's

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pretty much it.

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So once again I got a bigger because the changes we're making here you've made a lot of video courses

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over time and the changes we just made it's extremely likely likely that you might have just accidentally

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made a typo somewhere inside of here.

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So if your application is not working after this then I can guarantee you you got a typo somewhere inside

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of here or somewhere up inside that switch statement.

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So please double check your code make sure you don't have any typos inside of here.

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It's going to save this I'll flip back over and we can once again do a test.

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It's all increased red.

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Yep definitely works.

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Increase blue.

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Yep definitely works and increased green.

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Yep definitely works as well.

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All right so that's pretty much it.

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So we've now condensed down all of our state logic we don't have any additional callbacks or any additional

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hard to read functions going on inside of here.

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We have only calls to set color and then inside of set color.

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We've got some well kind of challenging to read stuff but I'd say overall once you kind of get used

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to the syntax you can definitely understand what's going on.

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All right.

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So now we've fixed all this stuff up.

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Let's take a quick pause right here.

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There is technically one more little optimization we could make to this function so we'll take another

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pause when we come back the next video.

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We're going to take a look at one last way that we can fix all this stuff up just a little bit more

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than it is already.

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So I'll see you in just a minute.