[swift-evolution] Argument of '#selector' cannot refer to a property?

David Hart david at hartbit.com
Sun Feb 21 03:19:47 CST 2016

I’ve played with the new #selector syntax and am loving it. But I often want to use it as a way to provide strong-typing to APIs which require String representations of properties. For example:

class Model: NSObject {
	dynamic var firstName: String = ""
	dynamic var lastName: String = ""

extension Model {
	var jsonValue: [String:AnyObject] {
		return [
			#selector(self.firstName): firstName,
			#selector(self.lastName): lastName

extension Model {
	func modelWithName(name: String) {
		return Database.execute("SELECT * FROM Model WHERE \(#selector(self.firstName)) = ? OR \(#selector(self.lastName)) = ?")

But there are currently two problems with this:

1) The compiler doesn’t accept #selector of properties with the error message: Argument of '#selector' cannot refer to a property. What’s the reasoning for that?
2) Even if it did, I would still have the wrap #selector with NSStringFromSelector. It would be really convenient if Selector objects would convert to String. How is that possible?

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