) -> Result<(Vec<(Payload<T>, [u8; 32])>, Vec<onion_utils::OnionKeys>), secp256k1::Error> {
let num_hops = unblinded_path.len() + destination.num_hops();
let mut payloads = Vec::with_capacity(num_hops);
let mut onion_packet_keys = Vec::with_capacity(num_hops);
) -> Result<(Vec<(Payload<T>, [u8; 32])>, Vec<onion_utils::OnionKeys>), secp256k1::Error> {
let num_hops = unblinded_path.len() + destination.num_hops();
let mut payloads = Vec::with_capacity(num_hops);
let mut onion_packet_keys = Vec::with_capacity(num_hops);