Create string t from string s, keeping only digit characters 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
(require '[clojure.string :as str])
(let [s "1a22b3c4de5f6" t (str/replace s #"[^\d]" "")] (println t))
using System.Linq;
var t = string.Concat(s.Where(c => char.IsDigit(c)));
import "regexp"
re := regexp.MustCompile("[^\\d]") t := re.ReplaceAllLiteralString(s, "")
t = filter (`elem` ['0'..'9']) s
t = s.replace(/[^\d]/gm,"");
RegExpr
t := ReplaceRegExpr('[^\d]', s, '');
for i := 1 to length(s) do if s[i] in ['0'..'9'] then t := t + s[i];
my $t = $s; $t =~ s/\D+//g;
import re
t = re.sub(r"\D", "", s)
t = s.delete("^0-9")
let t: String = s.chars().filter(|c| c.is_digit(10)).collect();
No security, no password. Other people might choose the same nickname.