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

jaden lind
jaden lind
300 Points
Posted by 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

Juan Carlos Delgado Vidal
Juan Carlos Delgado Vidal
4,762 Points

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++
}
Michael Piercy
Michael Piercy
1,756 Points
Michael Piercy
Michael Piercy
1,756 Points

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

Try using 'var' instead.

var index = 0