Swift: How to loop through all characters in a string, and also determine what characters belongs to a specific subset

Question

This Python code loops through all characters in a string and prints out characters that belong to a specific subset.

str = "abcdefg12345"
for ch in str:
    if ch in "ab34":
        print( ch )

How can I translate that code into Swift?

Answer 1

You can create a Set to hold the characters you are searching for, and then use contains to test for inclusion:

let str = "abcdefg12345"
let searchSet = Set("ab34")
for ch in str {
    if searchSet.contains(ch) {
       println(ch)
    }
}