Survival.first_cand: def of unified-nsga-iii@0.2.2.0
Import: import unified-nsga-iii@0.2.2.0/survival.bend as Survival
Lines 494-501 of unified-nsga-iii@0.2.2.0/survival.bend: https://jend.leeeet.dev/read.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&start_line=494&end_line=501

import Base

# First remaining last-front index. Used when inNiche is empty
# (C# would throw; never pick a phantom combined-pool index 0).
def first_cand(cand: List<&2, Nat>) -> Nat:
  match cand:
    case Nil{}:
      0n
    case x <> _:
      x

Uses (2):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat