riverdelta/std/list.nil

type List[T] = struct {
    ptr: I32,
    len: I32,
    cap: I32,
};

function new(): List[Int] = (
    List { ptr: 0_I32, len: 0_I32, cap: 0_I32 }
);

function push(list: List[Int], elem: Int) = (
    growIfNeeded(list, 1_I32);
    let addr = list.ptr + (SIZEOF * list.len);
    __i64_store(addr, elem);
    list.len = list.len + 1_I32;
);

function debugPrint(list: List[Int]) = (
    let i = 0_I32;
    print("[");
    loop (
        if i >= list.len then (
            break;
        );
        let elem = __i64_load(list.ptr + (i * SIZEOF));
        std.printInt(elem);
        if (i + 1_I32) < list.len then print(", ");

        i = i + 1_I32;
    );
    std.println("]");
);

// PRIVATE:

global SIZEOF: I32 = 8_I32;
global ALIGNOF: I32 = 8_I32;

function growIfNeeded(list: List[Int], elems: I32) = (
    if (list.len + elems) < list.cap then (
        let newMemory = std.rt.alloc.allocate(SIZEOF * list.cap * 2_I32, ALIGNOF);
        let oldMemory = list.ptr;
        let amount = SIZEOF * list.len;
        std.rt.memcpy(newMemory, oldMemory, amount);

        if list.cap > 0_I32 then std.rt.alloc.deallocate(list.ptr, list.cap * SIZEOF);
    );
);