Survival.first_bag_ref: def of unified-nsga-iii@0.2.2.0
Import: import unified-nsga-iii@0.2.2.0/survival.bend as Survival
Lines 778-783 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=778&end_line=783

import Base

def first_bag_ref(bags: List<&2, Bag>) -> Nat:
  match bags:
    case Nil{}:
      0n
    case Bag{+ref, count, members} <> _:
      ref

Uses (3):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=Bag