WEBVTT

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Welcome! In the previous lectures, you've seen that "Switch" statement is very similar to an "if" statement.

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right?

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So there should be an else branch inside a switch statement.

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as well, right?

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Yes! that's right.

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Let's check it out.

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To keep it simple I removed the other case clauses from here.

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Now let's say that the user has requested an unknown city name

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So you want to display a message to the user that the program doesn't know about that city.

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Let's take a look at how to do that. first, 

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I'm going to change the name of the city to something unknown like Limbo.

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You may remember this name from the inception movie great movie by the way.

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Right.

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Anyways, now I'm going to add a default clause here, like this.

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So when no case is matched to the given city and this default clause will be executed instead. OK let's

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print the message when the program can't find the city like this. OK!

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That's it.

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Now let's take a look at this.

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in the coding editor. right

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coding time as usual.

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Here it is. OK!

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First, let me write without a default clause.  `go run main.go Limbo`. as you can see it prints nothing.

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when  I give it Limbo.

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It's because none of the cases  matched to limbo.

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That's normal.

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Now lets add the default clause to the switch. Here I'm gonna type default with an ending colon

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like the case clauses like this.

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then I am gonna print a message.  fmt.Println("Where?")

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All right.

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Now let's run it again.

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as you can see this time it's prints where. here none of the cases  matched to limbo.

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Right.

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There are only Paris and Tokyo.

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So since it couldn't find a matching case and this default clause is executed instead. its that simple.

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by the way, you can move the default clause to anywhere inside the switch statement like this.

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It'll work the same.

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All right, Lets try it.  As you can see it prints where again.

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Now this right part is this time it brings France.

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It still works! as you can see the default clause still runs the last.

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So it's location in the  switch statement doesn't matter.

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By the way, let me also tell you that the else branch in if statement there can be only one

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default clause.

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per statement. Let me type another default clause here.  as you can see go warns me that  there

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are multiple defaults here.

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So it doesn't allow me to do so.

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Let's take it back.

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So in summary the default clause is just like an else branch.

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in an iif statement that can be only one default clause and it will be executed if none of the cases

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match to the switch condition.

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All right.

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That's all for now.

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Thank you for watching.

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See in the next lecture, Bye Bye.