def not_empty
import mlbend-metrics@0.1.0.0/main.bend as MlbendMetricsimport Base
192# the number of pairs, or why there is no answer
193def not_empty(r: Result<&1, &1, Bad, Nat>) -> Result<&1, &1, Bad, Nat>:
194 match r:
195 case Done{+n}:
196 not_empty_of(Nat.is_eq(n, 0n), n)
197 case Fail{Mismatch{expected, got}}:
198 Fail{Mismatch{expected, got}}
199 case Fail{Empty{}}:
200 Fail{Empty{}}