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We can use if statements as a shorter way to write the equivalent of a match that only matches one case

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optionally if it can have an alt containing code to run if the pattern and the if left does not match.

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So as super simple example will say let dog two is equal to some pet that is a dog.

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And then if let some pet.

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That is a dog equals dog too.

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We will print out the animal is a dog.

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But if it's not a dog.

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Then we'll print out.

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Not a dog.

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So what's going on in here?

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So we're basically saying, hey, if some.

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Pet is a dog.

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Right.

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So this is the type we're looking for.

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And then we created a dog to the same type.

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So if it matches, print out the animal is a dog.

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Otherwise it's not a dog.

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So we know that this is going to print out the animal is a dog.

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But if we happen to make it a cat.

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Well, then we would expect the match up here to not match and we would expect it to print, not a dog,

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which is what happens.

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So.

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You can also extend this with elseif and elseif statements.

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So it all works the same as if we were just doing regular control flow statements.

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So we can also extend this or we can also use while loops.

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So let's create a stack and we'll call it a new vector.

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And then what we'll do is we'll put in a couple of values.

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They will change these two different numbers and now we'll execute a while.

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Let some top equals stack dot pop.

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Print out.

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Top.

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So what's going on here?

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So we created a new vector, pushed in three values of one, two and three.

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And then we're saying, Hey, pop the stack.

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And then while it is some number which in this case it will be some one sum to some three.

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So while it is some number, we want to print out that number that is being taken off the stack.

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And what do we get?

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We get 3 to 1, and that is because stacks are last in, first out.

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So I just wanted to show you these quick examples of other ways that we can use if.

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Examples or wallet in order to match on single statements and then execute some code based on those

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match statements.