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# NSMapTableValueCallBacks

The function pointers used to configure behavior of `NSMapTable` with respect to value elements within a map table.

```
struct NSMapTableValueCallBacks
```

## Overview

All functions must know the types of things in the map table to be able to operate on them. Sets of predefined call backs are described in [`NSMapTable`](/documentation/Foundation/NSMapTable).

## Relationships

### Conforms To

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

---

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