Kotlin: For-loop range must have an 'iterator()' method

Question

If I use var charSet = 1..10 it works, but when I am using the below code, I'm getting this error.

var charSet = "A".."Z"
for (value in charSet) {    
  println("$value")  
}

For-loop range must have an 'iterator()' method.

Please let me know how to resolve this.

Answer 1

charSet is a ClosedRange<String> and that type doesn't have iterator() function (but ex. IntRange does). You can either change your range to 'A'..'Z' or create an extension function ClosedRange<String>.iterator() which would return a Iterator. The error should then go away