<!--
{
  "availability" : [
    "iOS: 17.0.0 -",
    "iPadOS: 17.0.0 -",
    "macCatalyst: 17.0.0 -",
    "macOS: 14.0.0 -",
    "tvOS: 17.0.0 -",
    "visionOS: 1.0.0 -",
    "watchOS: 10.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Foundation",
  "identifier" : "/documentation/Foundation/PredicateExpressions/DictionaryKeySubscript",
  "metadataVersion" : "0.1.0",
  "role" : "Structure",
  "symbol" : {
    "kind" : "Structure",
    "modules" : [
      "Foundation"
    ],
    "preciseIdentifier" : "s:10Foundation20PredicateExpressionsO22DictionaryKeySubscriptV"
  },
  "title" : "PredicateExpressions.DictionaryKeySubscript"
}
-->

# PredicateExpressions.DictionaryKeySubscript

```
struct DictionaryKeySubscript<Wrapped, Key, Value> where Wrapped : PredicateExpression, Key : PredicateExpression, Wrapped.Output == [Key.Output : Value], Key.Output : Hashable
```

## Topics

### Initializers

[`init(wrapped: Wrapped, key: Key)`](/documentation/Foundation/PredicateExpressions/DictionaryKeySubscript/init(wrapped:key:))

### Instance Properties

[`let key: Key`](/documentation/Foundation/PredicateExpressions/DictionaryKeySubscript/key)

[`let wrapped: Wrapped`](/documentation/Foundation/PredicateExpressions/DictionaryKeySubscript/wrapped)

## Relationships

### Conforms To

[`Escapable`](/documentation/Swift/Escapable)

[`StandardPredicateExpression`](/documentation/Foundation/StandardPredicateExpression)

[`Sendable`](/documentation/Swift/Sendable)

[`Decodable`](/documentation/Swift/Decodable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`Encodable`](/documentation/Swift/Encodable)

[`Copyable`](/documentation/Swift/Copyable)

[`PredicateExpression`](/documentation/Foundation/PredicateExpression)

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)