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iOS Swift Basics (retired) Control Flow While and Do-While Loop

Robert Hendricks
Robert Hendricks
609 Points

my code works in play ground but doesn't compile in the test area!

let numbers = [1,2,3,4,5,6,7,8,9,10]
index = 0
do {
       println(numbers[index])
        index++
} while index < numbers.count
while_loops.swift
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
index = 0
do {println(numbers[index])
    index++
    } while index < numbers.count

2 Answers

Michael Hulet
Michael Hulet
47,912 Points

It looks like you didn't declare index before using it. Playgrounds are rather lenient on this sometimes, but you're never actually going to launch code designed to run in a Playground. Here's a fixed version (probably):

while_loops.swift
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
//Notice the var keyword here
var index = 0
do {
    println(numbers[index])
    index++
} while index < numbers.count
Robert Hendricks
Robert Hendricks
609 Points

Thanks -- forgot to declare with var!