PredicateExpression

protocol · iOS 17.0+ · SDK 27.1

protocol PredicateExpression<Output>

A component expression that makes up part of a predicate. To transform a predicate, define a protocol for the result and add conformance on each predicate expression type that you support. For example: ```swift protocol ProsePredicateExpression { func proseQuery() -> String } // Repeated for each supported operator. extension PredicateExpressions.Equal: ProsePredicateExpression where LHS: ProsePredicateExpression, RHS: ProsePredicateExpression { func proseQuery() -> String { return lhs.proseQuery() + " is equal to " + rhs.proseQuery() } } extension Predicate { func proseQuery() -> String? { guard let expression = expression as? ProsePredicateExpression else { return nil } return expression.proseQuery() } } ```

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This type has no directly callable members in this snapshot. See the framework’s skipped declarations for unsupported APIs.

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