PROOF.off.at_take: def of bend-osdev-bytes@0.1.1.0
Import: import bend-osdev-bytes@0.1.1.0/PROOF.bend as PROOF
Lines 961-974 of bend-osdev-bytes@0.1.1.0/PROOF.bend: https://jend.leeeet.dev/read.txt?path=bend-osdev-bytes@0.1.1.0/PROOF.bend&start_line=961&end_line=974

import Base
import bend-osdev-bytes@0.1.1.0/bytes.bend as B

def off.at_take(+i: Nat, +n: Nat, ws: List<&2, B.OctByte>) -> {Nat.is_lt(i, n) == True{} : Bool} -> {B.w8s.at(B.w8s.drop(i, B.w8s.take(n, ws))) == B.w8s.at(B.w8s.drop(i, ws)) : Maybe<&2, U32>}:
  match i n ws:
    case 0n 0n _:
      h => off.no({B.w8s.at(Nil{}) == B.w8s.at(ws) : Maybe<&2, U32>}, h)
    case 1n+p 0n _:
      h => off.no({B.w8s.at(B.w8s.drop(1n+p, Nil{})) == B.w8s.at(B.w8s.drop(1n+p, ws)) : Maybe<&2, U32>}, h)
    case 0n 1n+q Nil{}:
      h => {==}
    case 0n 1n+q Con{x, t}:
      h => {==}
    case 1n+p 1n+q Nil{}:
      h => {==}
    case 1n+p 1n+q Con{x, t}:
      h => off.at_take(p, q, t, h)

Uses (11):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/PROOF.bend&name=off.no
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=OctByte
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=w8s.at
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=w8s.drop
  https://jend.leeeet.dev/definition.txt?path=bend-osdev-bytes@0.1.1.0/bytes.bend&name=w8s.take