def p_len_slice_le

bend-osdev-bytes@0.1.1.0 · PROOF.bend:1115

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

1115def p_len_slice_le(+i: Nat, +n: Nat, +o: B.Octets, h: {Nat.is_le(Nat.add(i, n), B.Octets.len(o)) == True{} : Bool}) -> {B.Octets.len(B.Octets.slice(i, n, o)) == n : Nat}:
1116  Equal.trans(Nat, B.Octets.len(B.Octets.slice(i, n, o)), Nat.min(n, Nat.sub(B.Octets.len(o), i)), n, p_len_slice(i, n, o), off.min_le(n, Nat.sub(B.Octets.len(o), i), off.le_sub(i, n, B.Octets.len(o), h)))