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# init(format:arguments:)

Creates the expression with the specified expression format and arguments list.

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

## Parameters

`expressionFormat`

The expression format.

`argList`

A list of arguments to be inserted into the `expressionFormat` string. The argument list is terminated by `nil`.

## Return Value

An initialized `NSExpression` object with the specified arguments.

## See Also

[`expressionWithFormat:`](/documentation/Foundation/NSExpression/expressionWithFormat:)

Creates the expression with the specified expression arguments.


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