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# reserveCapacity(_:)

Reserves enough space to store the specified number of key-value pairs.

```
mutating func reserveCapacity(_ minimumCapacity: Int)
```

## Parameters

`minimumCapacity`

The requested number of key-value pairs to
store.

## Discussion

If you are adding a known number of key-value pairs to a dictionary, use this
method to avoid multiple reallocations. This method ensures that the
dictionary has unique, mutable, contiguous storage, with space allocated
for at least the requested number of key-value pairs.

Calling the `reserveCapacity(_:)` method on a dictionary with bridged
storage triggers a copy to contiguous storage even if the existing
storage has room to store `minimumCapacity` key-value pairs.

---

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