def p_take_append_le

bend-osdev-bytes@0.1.1.0 · PROOF.bend:1180

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

1180def p_take_append_le(+n: Nat, +a: B.Octets, +b: B.Octets) -> {Nat.is_le(n, B.Octets.len(a)) == True{} : Bool} -> {B.Octets.take(n, B.Octets.append(a, b)) == B.Octets.take(n, a) : B.Octets}:
1181  match a b:
1182    case B.Octets{+xs} B.Octets{+ys}:
1183      h => q_take_app_le(n, xs, ys, off.len_fast_le(n, xs, h))