// RUN: %target-swift-frontend -typecheck -verify %s // REQUIRES: concurrency // https://github.com/apple/swift/issues/59909 struct Future { } extension Future { @preconcurrency func flatMap(_ callback: @escaping @Sendable (T) -> Future) -> Future { // #1 fatalError() } @preconcurrency public func flatMapErrorThrowing(_ callback: @escaping @Sendable (Error) throws -> T) -> Future { fatalError("") } } extension Future { @available(*, deprecated, message: "") func flatMap(file: StaticString = #file, line: UInt = #line, _ callback: @escaping (T) -> Future) -> Future { // #2 return self.flatMap(callback) } @inlinable @available(*, deprecated, message: "Please don't pass file:line:, there's no point.") public func flatMapErrorThrowing(file: StaticString = #file, line: UInt = #line, _ callback: @escaping (Error) throws -> T) -> Future { return self.flatMapErrorThrowing(callback) } }