A generic box type for adding unchecked Sendable conformance to a type

UnsafeSendableBox.swift

@dynamicMemberLookup
final class UnsafeSendableBox<T>: @unchecked Sendable {
	let value: T
	init(_ value: T) {
		self.value = value
	}

	subscript<Value>(dynamicMember keyPath: KeyPath<T, Value>) -> Value {
		value[keyPath: keyPath]
	}

	subscript<Value>(dynamicMember keyPath: ReferenceWritableKeyPath<T, Value>) -> Value {
		get { value[keyPath: keyPath] }
		set { value[keyPath: keyPath] = newValue }
	}
}

extension UnsafeSendableBox where T: DispatchSourceMemoryPressure {
	func activate() {
		value.activate()
	}
}