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Topic

functional

A collection of 5 issues

Why Apple?

Warn This post is not intend to argue any programming language. Barely related, it would be human language. Before you continue to read, I should warn you first. The following context may require a little foundation knowledge of functional programming and Swift, but not necessary. For someone only care about

Throw inside a do block and catch it back in Swift? Yes

Lazy forks, it's just simple topic, but I did the experiment for you: enum SomeError: Error { case notBig case veryBig } func someErrorFucntion() { do { throw SomeError.veryBig } catch { print(error.localizedDescription) } } someErrorFucntion() // And it will print veryBig!!

Fewer "guard" more flatMap

Swift's guard syntax is good, I admitted. But it's not always the best choice in some cases. Let's consider: something.callback() { someOther:SomeOther? in guard let someOther = someOther else { return } functionTakeSomeOther(someOther) } Indeed, "optional chaining" provide us a more convenience way to achieve the same goal with fewer

Map Map Map better in Swift

Map function is quite a convenience method that often used in functional(mainly) programming. In Swift, all collection types(Array,Dictionary,Set...) support map. It take a closure that take element type from T and output type U then transform from [T] to [U]. In most case, you will see

書單紙

書讀唔多，只講最正： Programming: The Swift Programming Language 1,2,2.2 Objective-C Programming Language 2.0 Edition Seven Programming Language in Seven Week Think functional Functional Programming with Swift C程序設計三十日自制操作系統 Code Code complete(ing) Zero to one (其實應該放落文化) Algorithm及Structure類睇得好雜同散，亦都無一本本頭到尾咁睇，就費事講。設計視覺：設計中的設計明室攝影札記論攝影設計的界限犬之記憶 Another