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# init(format:arguments:)

Creates a predicate by substituting the values in an argument list into a format string and parsing the result.

```
init(format predicateFormat: String, arguments argList: CVaListPointer)
```

## Parameters

`predicateFormat`

The format string for the new predicate.

`argList`

The arguments to substitute into `predicateFormat`. Values are substituted in the order they appear in the argument list.

## Return Value

A new predicate by substituting the values in `argList` into `predicateFormat` and parsing the result.

## Discussion

For details of the format of the format string and of limitations on variable substitution, see [Predicate Format String Syntax](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Predicates/Articles/pSyntax.html#//apple_ref/doc/uid/TP40001795).

---

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