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So in this lecture, I want to look at how and where we can use just additional patterns and the type

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of syntax is we have available to us.

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So there are many different syntax and ways that we can.

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Create a match arm.

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But I just want to introduce you to a few, just to kind of show you what all is available to us.

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So let's create a variable X and assign it to one.

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And then we're going to match on X.

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And then inside here we want to say one or two.

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So if the value of X is one or two, then we want to print out one or two.

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And then to make our match exhaustive, we want to say anything else.

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Let's print out.

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Not one or two.

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So when we run this with X being one, we expect it to print out one or two, which is exactly what

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happens.

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And then just to verify that we are getting the desired behavior, change X to ten and rerun it, and

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we see that we get not one or two.

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So this syntax up here with this operator is the OR call the OR operator, I should say.

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And what it's doing is it is saying, hey, if X is one or two.

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Then.

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This statement is true.

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So execute the following code, which is exactly what happened.

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So let's comment that out and let's look at a different way.

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So now we're going to match on.

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An exclusive range of values so we'll leave x is equal to ten will match on X again.

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And in this case, we'll say 1 to 5.

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And if it matches in that range, we'll print out matches.

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Otherwise we're going to print out.

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Not matching.

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So we see that we've got our little red squiggly.

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Let's check out what it says.

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And it's telling us the exclusive range pattern is experimental.

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So to fix this, we need to add in the little equal sign.

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So now it's going to be 1 to 5, which includes five.

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So with our X being ten, we expect this to print out, not matching.

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But when we go to five, I anticipate it saying that it matches, which is exactly what happened.

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So this is how we can use an inclusive range to check over a a range of values to see if something matches.

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And then lastly, we can use an if an excuse me and if condition specified after the pattern and a match.

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So let's check this out.

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So let's say let x equals to sum five and then we'll say let y equals five, and then we're going to

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match on x.

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And we'll say some ten.

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And then we're going to print out ten, but then we're going to do some x.

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If X equals Y, then we want to print out.

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Matches.

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And then otherwise, we just want to print out our default statement and for ease, we'll just print

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out default.

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So now we have some five Y equals to five and we're going to match on X.

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So when we run this, we see that it says it matches.

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So how is this working?

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So we're passing in X to our match statement and then X is some value and then X is in here as well,

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which in this case it is going to be five.

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So if five, which is referring to this x right here, equals y, which is five.

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Then in this case, we know that five equals five.

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So.

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We are able to execute this block of code.

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So now if I change this to ten.

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So X is going to be some ten, then we anticipate ten being printed out.

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Which is exactly what happens.

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And then obviously, if I put in 15 here, so we're not going to.

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This is going to be false.

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This will be false.

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Well, then we expect default to be printed and that's what we get.

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So through the last few lectures we have learned about idioms and pattern matching, which is a very

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powerful feature Rust has.

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And as I mentioned earlier, we were going to cover generics in the next section.

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So let's continue on with what traits and generics are.