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# init(forAggregate:)

Creates an aggregate expression for a specified collection.

```
init(forAggregate subexpressions: [NSExpression])
```

## Parameters

`subexpressions`

A collection object (an instance of `NSArray`, `NSSet`, or `NSDictionary`) that contains further expressions.

## Return Value

A new expression that contains the expressions in `collection`.

---

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