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# NSMapMember(_:_:_:_:)

Indicates whether a given table contains a given key.

```
func NSMapMember(_ table: NSMapTable<AnyObject, AnyObject>, _ key: UnsafeRawPointer, _ originalKey: UnsafeMutablePointer<UnsafeMutableRawPointer?>?, _ value: UnsafeMutablePointer<UnsafeMutableRawPointer?>?) -> Bool
```

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> if `table` contains a key equal to `key`, otherwise <doc://com.apple.documentation/documentation/Swift/false>.

## Discussion

If `table` contains a key equal to `key`, `originalKey` is set to `key`, and `value` is set to the value that `table` maps to `key`.

## See Also

[`NSNextMapEnumeratorPair`](/documentation/Foundation/NSNextMapEnumeratorPair(_:_:_:))

Returns a Boolean value that indicates whether the next map-table pair in the enumeration are set.

[`NSAllMapTableValues`](/documentation/Foundation/NSAllMapTableValues(_:))

Returns all of the values in the specified table.

[`NSMapGet`](/documentation/Foundation/NSMapGet(_:_:))

Returns a map table value for the specified key.

[`NSEnumerateMapTable`](/documentation/Foundation/NSEnumerateMapTable(_:))

Creates an enumerator for the specified map table.

[`NSAllMapTableKeys`](/documentation/Foundation/NSAllMapTableKeys(_:))

Returns all of the keys in the specified map table.


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