Xcode 8 :function types cannot have argument label breaking my build

Question

It seems that for some reason Swift have chosen to make coding in it less readable by forcing users to remove completion handler parameter labels. I have read the Swift discussion and still think it's a mistake. At least they could have made it optional.

When building using Xcode 8 - is there a way to force the compiler to use Swift 2.3 so I don't get these errors anymore? I have updated the option to use legacy Swift (under build settings) but I still seem to get this error:

Function types cannot have argument label 'isloggedIn'; use '_' instead

How can I keep my labels in my completion handlers?

Answer 1

The Swift designers decided to prohibit argument labels for function types.

The reasoning is explained here: https://github.com/apple/swift-evolution/blob/master/proposals/0111-remove-arg-label-type-significance.md

This is a frustrating and questionable choice, as prohibiting argument labels makes it much easier to incorrectly invoke closures, which seems more important than simplifying the language's type system.

Usability > ideology.