Survival.bags_kept: def of unified-nsga-iii@0.2.2.0
Import: import unified-nsga-iii@0.2.2.0/survival.bend as Survival
Lines 853-858 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=853&end_line=858

import Base

def bags_kept(+ref: Nat, +count: Nat, members: List<&2, MRow>, rest: List<&2, Bag>) -> List<&2, Bag>:
  match members:
    case Nil{}:
      rest
    case +m <> +ms:
      Bag{ref, 1n+count, {m <> ms : List<&2, MRow>}} <> rest

Uses (4):
  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
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=MRow