How to remove all characters from a string, except the integers?

[forkit]

On Thursday, 3 March 2022 at 19:28:36 UTC, matheus wrote:
>
> I'm a simple man who uses D with the old C mentality:
>
> import std.stdio;
>
> void main(){
>     string s, str = "4A0B1de!2C9~6";
>     foreach(i;str){
>         if(i < '0' || i > '9'){ continue; }
>         s ~= i;
>     }
>     writeln("Result: ", s);
> }
>
> Result: 401296
>
> Matheus.

mmm..but we no longer live in simple times ;-)

(i.e. unicode)