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# error: '([T]) -> U' is not convertible to '(T)

First time working with generics in swift, couldn't figure out how to fix it. I understand what the error is about but couldn't find the right syntax to express what I'm trying to do. How can I pass an array to transformation if the parameter inside is a type T and not an array of T? I came up with this solution:

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

return transformation(array)
}

func squaredElements(array: [Int]) -> [Int]{
var squaredArr = [Int]()
for i in 0...array.count-1{
squaredArr.append(array[i]*array[i])
}
return squaredArr
}

var arr = [1,2,3,4,5]

map(array: arr, transformation: squaredElements)
```

Does exactly what is asked to the quiz, but in other way. But doesn't solve the question as is asked.

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

return transformation(array)
}

//func squaredElements(array: [Int]) -> [Int]{
//    var squaredArr = [Int]()
//    for i in 0...array.count-1{
//        squaredArr.append(array[i]*array[i])
//    }
//    return squaredArr
//}
```

MOD

Pretty close. It looks like you missed that you are supposed to loop over the `array` argument and call `transformation` on each of the elements, then return the transformed items.

Hope this helps!

Thank you, Caleb. This was very helpful! I don't know why I didn't though about looping inside the generic function!

```func map<T, U>(array: [T], transformation: (T) -> U) -> [U] {
var newArray = [U]()
for element in array{
newArray.append(transformation(element))
}
return newArray
}
```

Now it's correct! Thank you again!