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# didValue(forInputKeyChange:)

Returns whether the input port value changed since the last execution of the custom patch.

```
func didValue(forInputKeyChange key: String!) -> Bool
```

## Parameters

`key`

The key for the input port whose value you want to check.

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> if the value on the input port changed since the last time the [`execute(_:atTime:withArguments:)`](/documentation/Quartz/QCPlugIn/execute(_:atTime:withArguments:)) method was called; always returns <doc://com.apple.documentation/documentation/Swift/false> if called outside of the `execute:atTime:withArguments:` method.

---

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