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Andrea Miotto
iOS Development Techdegree Graduate 23,357 PointsResult of call to 'addChoice(title:page:) is unused
Maybe I have a new versione of Xcode, but addChoice() return a Page type. When we call addChoice() like this:
homeward.addChoice(title: "Head back to Mars", page: touchdown)
I have the warning:
Result of call to 'addChoice(title:page:) is unused
Is there a better way? I don't like to have warnings :P
1 Answer
Michael Hulet
47,913 PointsIf it's warning you that you don't use the result, you can silence that warning by assigning it to an underscore constant, like this:
let _ = homeward.addChoice(title: "Head back to Mars", page: touchdown)
That'll tell Swift that you really don't want to use the result of calling that function, and it doesn't need to warn you about it. That being said, the _ constant/variable is basically just a garbage can. You can assign to it all you want, but you can never read from it in a normal app
Andrea Miotto
iOS Development Techdegree Graduate 23,357 PointsAndrea Miotto
iOS Development Techdegree Graduate 23,357 PointsIsn't a waste of memory?
Michael Hulet
47,913 PointsMichael Hulet
47,913 PointsNope. Swift doesn't actually keep track of what's in the
_variable. When you assign to it, you're just tossing whatever you're assigning to it into computational oblivion