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# init(containerClassDescription:containerSpecifier:key:index:)

Initializes an allocated [`NSIndexSpecifier`](/documentation/Foundation/NSIndexSpecifier) object with a class description, container specifier, collection key, and object index.

```
init(containerClassDescription classDesc: NSScriptClassDescription, containerSpecifier container: NSScriptObjectSpecifier?, key property: String, index: Int)
```

## Parameters

`classDesc`

Description for the container of the collection.

`container`

Container of the collection.

`property`

Name of the collection.

`index`

The object within the `key` collection the index specifier is to identify.

## Return Value

Initialized [`NSIndexSpecifier`](/documentation/Foundation/NSIndexSpecifier) object with its `index` property set to `objectIndex`.

## Discussion

Invokes the super class’s [`init(containerClassDescription:containerSpecifier:key:)`](/documentation/Foundation/NSScriptObjectSpecifier/init(containerClassDescription:containerSpecifier:key:)) method and sets the `index` property of the index specifier to `objectIndex`.

## See Also

  [Cocoa Scripting Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/ScriptableCocoaApplications/SApps_intro/SAppsIntro.html#//apple_ref/doc/uid/TP40002164)


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