ProofGen.rsum: def of minebender-game@1.0.0.0
Import: import minebender-game@1.0.0.0/proof_gen.bend as ProofGen
Lines 1057-1063 of minebender-game@1.0.0.0/proof_gen.bend: https://jend.leeeet.dev/read.txt?path=minebender-game@1.0.0.0/proof_gen.bend&start_line=1057&end_line=1063

import Base

# Each row near the first click's row, counted c times.
def rsum(+fy: Nat, +c: Nat, ys: List<&2, Nat>) -> Nat:
  match ys:
    case Nil{}:
      0n
    case y <> t:
      Nat.add(Bool.pick(Nat, nr(fy, y), c, 0n), rsum(fy, c, t))

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  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=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=minebender-game@1.0.0.0/proof_gen.bend&name=nr