Survival.pick_among.nrows: def of unified-nsga-iii@0.2.2.0
Import: import unified-nsga-iii@0.2.2.0/survival.bend as Survival
Lines 638-646 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=638&end_line=646

import Base
import unified-nsga-iii@0.2.2.0/rng.bend as Rng

def pick_among.nrows(+rows: List<&2, NRow>, n: Nat, +fallback: Nat, rng: Rng.State) -> Rng.State:
  match n:
    case 0n:
      Rng.with_k(rng, fallback)
    case 1n:
      Rng.with_k(rng, first_row_i(rows))
    case 1n+p:
      +rng2 = Rng.next_nat(rng, 1n+p)
      Rng.with_k(rng2, nrow_i(get_nrow(rows, Rng.last_nat(rng2))))

Uses (10):
  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/rng.bend&name=State
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/rng.bend&name=last_nat
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/rng.bend&name=next_nat
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/rng.bend&name=with_k
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=NRow
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=first_row_i
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=get_nrow
  https://jend.leeeet.dev/definition.txt?path=unified-nsga-iii@0.2.2.0/survival.bend&name=nrow_i