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// RUN: %target-run-simple-swift
// REQUIRES: executable_test
enum E {
protocol P {}
}
struct Conforms {}
extension Conforms: E.P {}
struct DoesNotConform {}
struct S<T> {}
extension S: E.P where T: E.P {}
@inline(never)
func castToNested(_ value: Any) -> (any E.P)? {
value as? any E.P
}
// Regular conformance.
precondition(castToNested(Conforms()) != nil)
precondition(castToNested(DoesNotConform()) == nil)
// Conditional conformance.
precondition(castToNested(S<Conforms>()) != nil)
precondition(castToNested(S<DoesNotConform>()) == nil)
// Verify that 'E.P' and a non-nested 'P' are different.
protocol P {}
@inline(never)
func castToNonNested(_ value: Any) -> (any P)? {
value as? any P
}
precondition(castToNonNested(Conforms()) == nil)
precondition(castToNonNested(S<Conforms>()) == nil)
precondition(castToNonNested(DoesNotConform()) == nil)
precondition(castToNonNested(S<DoesNotConform>()) == nil)
// Local protocols.
@inline(never)
func f0(_ input: Any) -> (Any, inputConforms: Bool) {
protocol LocalProto { }
struct ConformsToLocal: LocalProto {}
if let input = input as? any LocalProto {
return (input, true)
} else {
return (ConformsToLocal(), false)
}
}
var result = f0(DoesNotConform())
precondition(result.inputConforms == false)
result = f0(result.0)
precondition(result.inputConforms == true)
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