---
title: "init(_:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/objectidentifier/init(_:)-223xw"
---

# init(_:)

Creates an instance that uniquely identifies the given class instance.

## Declaration

```swift
init(_ x: AnyObject)
```

## Parameters

- `x`: An instance of a class.

## Discussion

Discussion The following example creates an example class IntegerRef and compares instances of the class using their object identifiers and the identical-to operator (===): class IntegerRef {     let value: Int     init(_ value: Int) {         self.value = value     } }

let x = IntegerRef(10) let y = x

print(ObjectIdentifier(x) == ObjectIdentifier(y)) // Prints "true" print(x === y) // Prints "true"

let z = IntegerRef(10) print(ObjectIdentifier(x) == ObjectIdentifier(z)) // Prints "false" print(x === z) // Prints "false"