Argon2.prev_index: def of bend-collections-laws-crypto@1.0.0.0
Import: import bend-collections-laws-crypto@1.0.0.0/src/crypto/argon2/argon2.bend as Argon2
Lines 219-224 of bend-collections-laws-crypto@1.0.0.0/src/crypto/argon2/argon2.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-crypto@1.0.0.0/src/crypto/argon2/argon2.bend&start_line=219&end_line=224

import Base

def prev_index(+l: Nat, +q: Nat, +j: Nat, first: Bool) -> Nat:
  match first:
    case True{}:
      Nat.add(Nat.mul(l, q), Nat.sub(q, 1n))
    case False{}:
      Nat.sub(Nat.add(Nat.mul(l, q), j), 1n)

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  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=Base/base.bend&name=Nat.mul
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.sub