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Start your free trialSam Belcher
3,719 PointsGeneric Functions With Multiple Type Paremeters
I'm confused with why "append" isn't working and I am also not sure how to return a value of type "[U]"
func map<T, U>(array: [T], transformation: (T) -> U) -> [U] {
var mapArray: [U] = []
for number in array {
return mapArray.append(transformation(number))
}
}
1 Answer
Magnus Hållberg
17,232 PointsIts not the append that is the problem, its where you are trying to return. You need to return the array after the new values are appended, now you are trying to appen each new value from the loop. Try to return the array after the loop.