PROOF.off.at_app_lt: def of bend-osdev-bytes@0.1.1.0
Import: import bend-osdev-bytes@0.1.1.0/PROOF.bend as PROOF
Lines 950-959 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=950&end_line=959

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

def off.at_app_lt(+i: Nat, xs: List<&2, B.OctByte>, +ys: List<&2, B.OctByte>) -> {Nat.is_lt(i, List.length(&2, B.OctByte, xs)) == True{} : Bool} -> {B.w8s.at(B.w8s.drop(i, List.append(&2, B.OctByte, xs, ys))) == B.w8s.at(B.w8s.drop(i, xs)) : Maybe<&2, U32>}:
  match i xs:
    case 0n Nil{}:
      h => off.no({B.w8s.at(ys) == None{} : Maybe<&2, U32>}, h)
    case 1n+p Nil{}:
      h => off.no({B.w8s.at(B.w8s.drop(1n+p, ys)) == None{} : Maybe<&2, U32>}, h)
    case 0n Con{x, t}:
      h => {==}
    case 1n+p Con{x, t}:
      h => off.at_app_lt(p, t, ys, h)

Uses (12):
  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=List.append
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.length
  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