Learning Swift by Developing Haneke

Given at NSSpain 2014.

Source and image attribution at: https://github.com/Haneke/Assets/blob/master/Talks/NSSpain%202014.md

Transcript

1. LEARNING SWIFT BY DEVELOPING HANEKE
3. github.com/Haneke
4. A lightweight zero-config image cache for iOS. [imageView hnk_setImageFromURL:url];
5. ▸ Asynchronous image retrieval ▸ First-level memory cache using NSCache ▸ Second-level LRU disk cache using the file system ▸ Background image resizing ▸ Image decompression ▸ Optimized for UITableView and UICollectionView cell reuse
6. HANEKE 1.0.0 ▸ UIButton category ▸ Independent LRU disk cache ▸ Optional AFNetworking integration ▸ Audited APIs and documentation ▸ Fully unit tested (until proven otherwise) AVAILABLE TODAY
7. @oriolblanc @joanromano @lascorbe @hpique github.com/realm/summer-of-swift
8. HANEKE<T> v0.1.0
9. A lightweight generic cache for iOS, in Swift. let cache = Cache<UIImage>("images") With all the features of its Objective-C counterpart* imageView.hnk_setImageFromURL(url)
10. let cache = Cache<UIImage>("images") let cache = Cache<NSData>("data") let cache = Cache<String>("text")
11. FEATURING
12. SQL GENERICS class Cache<T : DataConvertible where T.Result == T> {...} protocol DataConvertible { typealias Result class func convertFromData(data:NSData) -> Result? } stackoverflow.com/questions/25922152/not-identical-to-self stackoverflow.com/questions/25915306/generic-closure-in-protocol
13. MIKE ASH CODE func getKey() -> COpaquePointer { let ptr: COpaquePointer = Unmanaged<AnyObject>.passUnretained(self).toOpaque() return ptr }
14. THE AMAZING UNDERSCORE BAD dispatch_sync(sut.cacheQueue, { fileManager.removeItemAtPath(path, error: &error) }) GOOD dispatch_sync(sut.cacheQueue, { let _ = fileManager.removeItemAtPath(path, error: &error) })
15. MUTANT NINJA TUPLES func onMemoryWarning() { for (_, (_, memoryCache, _)) in self.formats { memoryCache.removeAllObjects() } }
16. AND MORE ▸ @autoclosures to optimize performance ▸ test expectations ▸ mocking with function classes ▸ bitwise operations ▸ structs as namespaces ▸ extensions ▸ interaction with C APIs
17. TAKEAWAYS
18. SWIFT IS NOT FINISHED
19. BAD let image = UIImage(data: data) GOOD if let image : UIImage! = UIImage(data: data) { ... }
20. CHANGE BEYOND FUNCTIONAL
21. from MUTABILITY to INMUTABILITY
22. from CLASSES to ANY
23. from VERBOSITY to INFERENCE
24. github.com/Haneke