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Douglas Aldridge
5,634 Pointscan anyone help I am stuck with intermediate swift - closures - functions Challenge 1 of 3
Challenge Task 1 of 3
In an extension to the String type, declare a function named transform. The function should accept as an argument another function of type (String) -> String. For this argument, let's omit the external label. The transform function should also return a String.
In the body of the method, return the result of applying the function argument to self.
I ended up with this (but its wrong):
extension String { func transform(argument: (String) -> String) -> String { return argument(self) } }
extension String {
func transform(argument: (String) -> String) -> String {
return argument(self)
}
}
2 Answers
Joe Beltramo
Courses Plus Student 22,191 PointsIt looks like the only part you are missing is the let's omit the external label.
In Swift you can omit labels by adding a _ before your argument, so:
func transform(_ argument: (String) -> String) -> String { ... }
This allows you to not need to specify the label name when calling the method: transform("someString") instead of transform(argument: "someString")
Douglas Aldridge
5,634 PointsThanks for the help Joe