108 lines
3.0 KiB
Zig
108 lines
3.0 KiB
Zig
const debug = @import("debug.zig");
|
|
const assert = debug.assert;
|
|
const mem = @import("mem.zig");
|
|
const Allocator = mem.Allocator;
|
|
|
|
pub fn ArrayList(comptime T: type) -> type{
|
|
struct {
|
|
const Self = this;
|
|
|
|
/// Use toSlice instead of slicing this directly, because if you don't
|
|
/// specify the end position of the slice, this will potentially give
|
|
/// you uninitialized memory.
|
|
items: []T,
|
|
len: usize,
|
|
allocator: &Allocator,
|
|
|
|
pub fn init(allocator: &Allocator) -> Self {
|
|
Self {
|
|
.items = []T{},
|
|
.len = 0,
|
|
.allocator = allocator,
|
|
}
|
|
}
|
|
|
|
pub fn deinit(l: &Self) {
|
|
l.allocator.free(l.items);
|
|
}
|
|
|
|
pub fn toSlice(l: &Self) -> []T {
|
|
return l.items[0..l.len];
|
|
}
|
|
|
|
pub fn toSliceConst(l: &const Self) -> []const T {
|
|
return l.items[0..l.len];
|
|
}
|
|
|
|
pub fn append(l: &Self, item: &const T) -> %void {
|
|
const new_item_ptr = %return l.addOne();
|
|
*new_item_ptr = *item;
|
|
}
|
|
|
|
pub fn appendSlice(l: &Self, items: []const T) -> %void {
|
|
%return l.ensureCapacity(l.len + items.len);
|
|
mem.copy(T, l.items[l.len..], items);
|
|
l.len += items.len;
|
|
}
|
|
|
|
pub fn resize(l: &Self, new_len: usize) -> %void {
|
|
%return l.ensureCapacity(new_len);
|
|
l.len = new_len;
|
|
}
|
|
|
|
pub fn resizeDown(l: &Self, new_len: usize) {
|
|
assert(new_len <= l.len);
|
|
l.len = new_len;
|
|
}
|
|
|
|
pub fn ensureCapacity(l: &Self, new_capacity: usize) -> %void {
|
|
var better_capacity = l.items.len;
|
|
if (better_capacity >= new_capacity) return;
|
|
while (true) {
|
|
better_capacity += better_capacity / 2 + 8;
|
|
if (better_capacity >= new_capacity) break;
|
|
}
|
|
l.items = %return l.allocator.realloc(T, l.items, better_capacity);
|
|
}
|
|
|
|
pub fn addOne(l: &Self) -> %&T {
|
|
const new_length = l.len + 1;
|
|
%return l.ensureCapacity(new_length);
|
|
const result = &l.items[l.len];
|
|
l.len = new_length;
|
|
return result;
|
|
}
|
|
|
|
pub fn pop(self: &Self) -> T {
|
|
self.len -= 1;
|
|
return self.items[self.len];
|
|
}
|
|
}
|
|
}
|
|
|
|
test "basic ArrayList test" {
|
|
var list = ArrayList(i32).init(&debug.global_allocator);
|
|
defer list.deinit();
|
|
|
|
{var i: usize = 0; while (i < 10) : (i += 1) {
|
|
%%list.append(i32(i + 1));
|
|
}}
|
|
|
|
{var i: usize = 0; while (i < 10) : (i += 1) {
|
|
assert(list.items[i] == i32(i + 1));
|
|
}}
|
|
|
|
assert(list.pop() == 10);
|
|
assert(list.len == 9);
|
|
|
|
%%list.appendSlice([]const i32 { 1, 2, 3 });
|
|
assert(list.len == 12);
|
|
assert(list.pop() == 3);
|
|
assert(list.pop() == 2);
|
|
assert(list.pop() == 1);
|
|
assert(list.len == 9);
|
|
|
|
%%list.appendSlice([]const i32 {});
|
|
assert(list.len == 9);
|
|
}
|