As_str for integers

I'm looking for ways to have str representations of ranges of integers without allocating. My current best attempt is to manually match on each value: match i { 0 => "0", 1 => "1", 2 => "2", ... n => "n" } which works, but has the obvious problem of not scaling. I've tried to automate this with macros, but i couldn't get it to work with declarative macros and procedural macros seemed too involved for me.