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| /// Returns a modified reference type | |
| public func with<T: AnyObject>(_ this: T, update: (T) throws -> Void) rethrows -> T { | |
| try update(this) | |
| return this | |
| } | |
| /// Returns a modified copy of a value type | |
| public func with<T>(_ item: T, update: (inout T) throws -> Void) rethrows -> T { | |
| var this = item | |
| try update(&this) | |
| return this | |
| } | |
| // Workaround not needed with removed inout for reference types | |
| /// Returns a modified copy of the instance | |
| /// | |
| /// - Warning: This variation is specific for reference | |
| /// items and includes a workaround for a Swift | |
| /// [bug](https://bugs.swift.org/browse/SR-2773) | |
| /// | |
| public func with<T: AnyObject>(_ item: T, | |
| update: (inout T) throws -> Void) rethrows -> T | |
| { | |
| var this = item | |
| try update(&this) | |
| // Bug workaround. When Swift is fixed, remove this | |
| // and remove the `AnyObject` constraint | |
| var ptr: Unmanaged<T>? = Unmanaged<T>.passRetained(this) | |
| .autorelease(); defer { ptr = nil } | |
| return this | |
| } |
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