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# formSymmetricDifference(_:)

Removes the elements of the set that are also in the given set and adds
the members of the given set that are not already in the set.

```
mutating func formSymmetricDifference(_ other: Self)
```

## Parameters

`other`

A set of the same type.

## Discussion

In the following example, the elements of the `employees` set that are
also members of `neighbors` are removed from `employees`, while the
elements of `neighbors` that are not members of `employees` are added to
`employees`. In particular, the names `"Bethany"` and `"Eric"` are
removed from `employees` while the name `"Forlani"` is added.

```
var employees: Set = ["Alicia", "Bethany", "Diana", "Eric"]
let neighbors: Set = ["Bethany", "Eric", "Forlani"]
employees.formSymmetricDifference(neighbors)
print(employees)
// Prints "["Diana", "Forlani", "Alicia"]"
```

---

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