What is the replacement for isDigit() for characters in Swift?

Question

As mentioned in this post, before Xcode 6 Beta 4, one could use c.isDigit() and c.isAlpha() to find if c : Character was a digit or al

Answer 1

Swift 3 seems a little easier:

let str = "abcdef12345"
let digitSet = CharacterSet.decimalDigits

for ch in str.unicodeScalars {
    if digitSet.contains(ch) {
        // is digit!
    }
}