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# CFRunLoopTimerIsValid(_:)

Returns a Boolean value that indicates whether a CFRunLoopTimer object is valid and able to fire.

```
func CFRunLoopTimerIsValid(_ timer: CFRunLoopTimer!) -> Bool
```

## Parameters

`timer`

The run loop timer to examine.

## Return Value

`true` if `timer` is valid; otherwise `false`.

## Discussion

A non-repeating timer is automatically invalidated after it fires.

---

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