def inc
import emerging-ezjson@1.3.0.0/src/fixed.bend as Fixedimport Base
230# one more on digits written last first
231def inc(digits: String) -> String:
232 match digits:
233 case SNil{}:
234 "1"
235 case SCon{+hd, +tl}:
236 inc.at(Char.is_eq(hd, '9'), hd, tl, _u => inc(tl))