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# NSMapInsert(_:_:_:)

Inserts a key-value pair into the specified table.

```
func NSMapInsert(_ table: NSMapTable<AnyObject, AnyObject>, _ key: UnsafeRawPointer?, _ value: UnsafeRawPointer?)
```

## Discussion

Inserts `key` and `value` into `table`. If `key` matches a key already in `table`, `value` is retained and the previous value is released, using the `retain` and `release` callback functions that were specified when the table was created. Raises `NSInvalidArgumentException` if `key` is equal to the `notAKeyMarker` field of the table’s [`NSMapTableKeyCallBacks`](/documentation/Foundation/NSMapTableKeyCallBacks) structure.

## See Also

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

Inserts a key-value pair into the specified table.

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

Removes a key and corresponding value from the specified table.

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

Inserts a key-value pair into the specified table if the pair had not been previously added.


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