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

Shane Hartman
Shane Hartman
1,534 Points
Posted by Shane Hartman
Shane Hartman
1,534 Points

My code runs correctly in xcode but it doesn't pass the review process

Here are two variations that both work:

func iMap<T, U>(_ array: Array<T>,_ transformation: (T) -> U) -> Array<U> { var transArray: [U] = [] for i in 0..<array.count { transArray.append(transformation(array[i])) } return transArray }

func square(_ first: Int) -> Int {

return first * first

}

iMap([1,2,3,4,5], square)

func map<T, U>(array: Array<T>,transformation: (T) -> U) -> Array<U> { var transArray: [U] = [] for i in 0..<array.count { transArray.append(transformation(array[i])) } return transArray } map(array: [1,2,3,4,5], transformation: square)

generics.swift 
func map<T, U>(_ array: Array<T>,_ transformation: (T) -> U) -> Array<U> {
    var transArray: [U] = []
    for i in 1...array.count {
        transArray.append(transformation(array[i]))
    }
    return transArray
}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Try this

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

    for values in array {
        newArray.append(transformation(values))
    }
    return newArray
}