iterator for chars in a string in swift
//iterator for chars in a string
struct StrIter {
let string:String
var current:String.Index
init(string:String) {
self.string = string
self.current = self.string.startIndex
}
mutating func next() -> Character? {
if self.current != self.string.endIndex {
let returned = self.string[self.current]
self.current = self.string.index(after: self.current)
return returned
}
else {
return nil
}
}
}