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

jaden lind
jaden lind
300 Points

while loops

When I try to create a while loop I keep getting this error-- cannot invoke '++' with an argument of type 'Int' index++-- I thought you need to create a false boolean expression to close the loop.

while_loops.swift
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

let index = 0

while numbers.count > index {
  println(numbers.count)
   index++
   }

2 Answers

You need to set index to a variable (var) so it can be modified

let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

var index = 0

while numbers.count > index {
    println(numbers.count)
    index++
}

You're currently using 'let' to set index to 0. This sets an immutable value.

Try using 'var' instead.

var index = 0