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iOS Swift Collections and Control Flow Control Flow With Loops Working With Loops

In code challenge, noted "preview" for compiler errors does not exist

In the code challenge step a simplified Swift Playground window is displayed. When "Check work" returns, "X Bummer!" the error requests user to "Please select preview to view the compiler error", but no such option (labeled "preview") exists in this window.

On top of that, when I run the code via an actual Swift Playground environment in Xcode, no error is returned. The code runs as expected.

Any ideas what's expected here?

loops.swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below
while count

while counter < numbers.count {
    sum = numbers.reduce(0, +)
    counter += 1
}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points

No need to use reduce as the task does not ask for that

let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below

while counter < numbers.count {

sum += numbers[counter]
counter += 1

}

I had the same problem. I got past it when I realized I was using parentheses instead of brackets for the array subscript. But the "Preview" tab that was present in earlier code challenges is not there on this one.