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# contains(_:)

Returns a Boolean value that indicates whether the given element exists
in the set.

```
func contains(_ member: Self.Element) -> Bool
```

## Parameters

`member`

An element to look for in the set.

## Return Value

`true` if `member` exists in the set; otherwise, `false`.

## Discussion

This example uses the `contains(_:)` method to test whether an integer is
a member of a set of prime numbers.

```
let primes: Set = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37]
let x = 5
if primes.contains(x) {
    print("\(x) is prime!")
} else {
    print("\(x). Not prime.")
}
// Prints "5 is prime!"
```

---

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