Rand.swap_at: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/src/math/random/rand.bend as Rand
Lines 281-283 of bend-collections-laws-math@1.0.0.0/src/math/random/rand.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/src/math/random/rand.bend&start_line=281&end_line=283

import Base
import bend-collections-laws-math@1.0.0.0/src/math/u64.bend as W
import bend-collections-laws-math@1.0.0.0/src/math/w64.bend as X

def swap_at(-A: Data, -S: Data, xs: List<&2, A>, +i: Nat, p: W.U64 & S) -> List<&2, A> & S:
  (+j, s) = p
  (swap(A, xs, i, X.n48(j)), s)

Uses (7):
  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=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/random/rand.bend&name=swap
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/u64.bend&name=U64
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/w64.bend&name=n48