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# PredicateError

An error thrown while evaluating a predicate.

```
struct PredicateError
```

## Topics

### Errors

[`static let forceCastFailure: PredicateError`](/documentation/Foundation/PredicateError/forceCastFailure)

[`static let forceUnwrapFailure: PredicateError`](/documentation/Foundation/PredicateError/forceUnwrapFailure)

[`static let invalidInput: PredicateError`](/documentation/Foundation/PredicateError/invalidInput)

[`static let undefinedVariable: PredicateError`](/documentation/Foundation/PredicateError/undefinedVariable)

## Relationships

### Conforms To

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

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

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

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

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

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

---

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