axelar-cgp-sui

Module 0x0::utils

Deepbook utility functions.

use 0x1::vector;

Function pop_until

Pop elements from the back of v until its length equals n, returning the elements that were popped in the order they appeared in v.

public(friend) fun pop_until<T>(v: &mut vector<T>, n: u64): vector<T>
Implementation 
public(package) fun pop_until<T>(v: &mut vector<T>, n: u64): vector<T> {
    let mut res = vector[];
    while (v.length() > n) {
        res.push_back(v.pop_back());
    };

    res.reverse();
    res
}

Function pop_n

Pop n elements from the back of v, returning the elements that were popped in the order they appeared in v.

Aborts if v has fewer than n elements.

public(friend) fun pop_n<T>(v: &mut vector<T>, n: u64): vector<T>
Implementation 
public(package) fun pop_n<T>(v: &mut vector<T>, n: u64): vector<T> {
    let mut res = vector[];
    n.do!(|_| res.push_back(v.pop_back()));
    res.reverse();
    res
}

Function encode_order_id

first bit is 0 for bid, 1 for ask next 63 bits are price (assertion for price is done in order function) last 64 bits are order_id

public(friend) fun encode_order_id(is_bid: bool, price: u64, order_id: u64): u128
Implementation 
public(package) fun encode_order_id(
    is_bid: bool,
    price: u64,
    order_id: u64,
): u128 {
    if (is_bid) {
        ((price as u128) << 64) + (order_id as u128)
    } else {
        (1u128 << 127) + ((price as u128) << 64) + (order_id as u128)
    }
}

Function decode_order_id

Decode order_id into (is_bid, price, order_id)

public(friend) fun decode_order_id(encoded_order_id: u128): (bool, u64, u64)
Implementation 
public(package) fun decode_order_id(encoded_order_id: u128): (bool, u64, u64) {
    let is_bid = (encoded_order_id >> 127) == 0;
    let price = (encoded_order_id >> 64) as u64;
    let price = price & ((1u64 << 63) - 1);
    let order_id = (encoded_order_id & ((1u128 << 64) - 1)) as u64;

    (is_bid, price, order_id)
}