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# FunctionIdentifier

A type that stores the designation code for one of your
vehicle’s features.

```
struct FunctionIdentifier
```

## Overview

A [`FunctionIdentifier`](/documentation/CarKey/FunctionIdentifier) type wraps a vehicle-specific code
you define. This code — known as the function identifier
— corresponds to a particular feature of your vehicle. For
example, one function identifier might represent the vehicle’s
door locks and another represent the vehicle’s window system.
Use this type in conjunction with an [`ActionIdentifier`](/documentation/CarKey/ActionIdentifier) type
to specify the complete action you want to perform on a vehicle.

## Topics

### Creating a Function Identifier

[`init(rawValue: Int)`](/documentation/CarKey/FunctionIdentifier/init(rawValue:))

Creates and returns a new function identifier with the specified value.

[`init(Int)`](/documentation/CarKey/FunctionIdentifier/init(_:))

Creates and returns a new function identifier with the specified value.

### Getting the Value

[`let rawValue: Int`](/documentation/CarKey/FunctionIdentifier/rawValue)

The raw value that corresponds to the specific feature of your vehicle.

## Relationships

### Conforms To

[`Hashable`](/documentation/Swift/Hashable)

[`Equatable`](/documentation/Swift/Equatable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

---

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