ProofSums.rsum_at: def of minebender-game@1.0.0.0
Import: import minebender-game@1.0.0.0/proof_sums.bend as ProofSums
Lines 79-84 of minebender-game@1.0.0.0/proof_sums.bend: https://jend.leeeet.dev/read.txt?path=minebender-game@1.0.0.0/proof_sums.bend&start_line=79&end_line=84

import Base

def rsum_at(~A: Data, ~f: A -> Nat, +d: A, +r: List<&2, A>, xs: List<&2, Nat>) -> Nat:
  match xs:
    case Nil{}:
      0n
    case x <> t:
      Nat.add(f(Maybe.default(&2, A, List.get(&2, A, r, x), d)), rsum_at(~A, ~f, d, r, t))

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.get
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe.default
  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