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iOS Generics in Swift Generic Functions, Parameters and Constraints CSS Background Blend Modes Challenge

Roland Schützenhofer
Roland Schützenhofer
4,311 Points
Posted by Roland Schützenhofer
Roland Schützenhofer
4,311 Points

Your code could not be compiled. But there aren't any Errors in the Preview Section.

func map<T,U>(array: [T], transformation: (T)->U, test: U) -> [U] { var resultArray: [U] = [] var counter = 0 for i in 1...array.count{ print(counter) resultArray.append(transformation(array[counter])) counter += 1 } return resultArray }

generics.swift 
func map<T,U>(array: [T], transformation: (T)->U, test: U) -> [U] {

    var resultArray: [U] = []
    var counter = 0
    for i in 1...array.count{
        print(counter)
        resultArray.append(transformation(array[counter]))
        counter += 1
    }
    return resultArray

}

1 Answer

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

You added an extra parameter to the function. Remove test and it will work:

 func map<T,U>(array: [T], transformation: (T)->U) -> [U] {

    var resultArray: [U] = []
    var counter = 0
    for i in 1...array.count{
        print(counter)
        resultArray.append(transformation(array[counter]))
        counter += 1
    }
    return resultArray

}