If I import UIKit in here, I get seemingly ridiculous errors: ============================= import Foundation import UIKit
if let url = NSURLComponents(string: "http://apple.com/foo/bar?q=123";) { let url2 = url url2.path = nil let url3 = url.copy() url3.path = nil } playground19.swift:10:2: error: ambiguous use of 'path' url3.path = nil ^ QuartzCore.CAKeyframeAnimation:4:13: note: found this candidate @objc var path: CGPath? { get set } ^ Foundation.NSURL:50:13: note: found this candidate @objc var path: String? { get } ^ ============================= Oh, right, it's AnyObject. But why doesn't it find the path on NSURLComponents? Remove the UIKit import, and it's better: ============================= import Foundation if let url = NSURLComponents(string: "http://apple.com/foo/bar?q=123";) { let url2 = url url2.path = nil let url3 = url.copy() url3.path = nil } playground20.swift:9:12: error: cannot assign to property: 'url3' is a 'let' constant url3.path = nil ~~~~ ^ /var/folders/16/jfb809_s2fz01ql7k494f6pc0000gn/T/./lldb/33089/playground20.swift:8:2: note: change 'let' to 'var' to make it mutable let url3 = url.copy() ^~~ var ============================= But why does it allow the url2.path assignment? Both of those are "let". Anyway, let's follow the compiler's advice: ============================= import Foundation if let url = NSURLComponents(string: "http://apple.com/foo/bar?q=123";) { let url2 = url url2.path = nil var url3 = url.copy() url3.path = nil } playground21.swift:9:12: error: cannot assign to property: 'url3' is immutable url3.path = nil ~~~~ ^ ============================= Nope, still no good. Let's cast things better: ============================= import Foundation if let url = NSURLComponents(string: "http://apple.com/foo/bar?q=123";) { let url2 = url url2.path = nil let url3 = url.copy() as! NSURLComponents url3.path = nil } ============================= No errors! But url3 is "let." Why is it allowed here? The final question: Is there a type-safe mutable copy in Swift that's not so verbose as copy-with-cast? -- Rick Mann rm...@latencyzero.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
