Rewrite WMBag in Rust.

We should eventually get rid of this entirely, in favor of something along the
lines of a sorted Vec that is fully typed (so the payload isn't just a void*).
This commit is contained in:
2025-10-28 21:13:31 -04:00
parent 46e540b1b1
commit 89183f3bcb
7 changed files with 402 additions and 543 deletions

View File

@@ -65,7 +65,6 @@ libWINGs_la_SOURCES = \
wwindow.c
libWUtil_la_SOURCES = \
bagtree.c \
error.c \
error.h \
findfile.c \

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@@ -173,7 +173,7 @@ typedef struct {
typedef int WMArrayIterator;
typedef void *WMBagIterator;
typedef int WMBagIterator;
typedef void WMNotificationObserverAction(void *observerData,
@@ -479,7 +479,7 @@ void* WMArrayPrevious(WMArray *array, WMArrayIterator *iter);
for (var = WMArrayLast(array, &(i)); (i) != WANotFound; \
var = WMArrayPrevious(array, &(i)))
/* ---[ WINGs/bagtree.c ]------------------------------------------------- */
/* ---[ wutil-rs/src/bag.rs ]------------------------------------------------- */
/*
* Tree bags use a red-black tree for storage.
@@ -498,9 +498,7 @@ WMBag* WMCreateTreeBag(void);
void* WMGetFromBag(WMBag *bag, int index);
void* WMReplaceInBag(WMBag *bag, int index, void *item);
#define WMSetInBag(bag, index, item) WMReplaceInBag(bag, index, item)
void WMSetInBag(WMBag *bag, int index, void *item);
void WMEmptyBag(WMBag *bag);
@@ -521,7 +519,7 @@ void* WMBagIteratorAtIndex(WMBag *bag, int index, WMBagIterator *ptr);
/* The following macro assumes that the bag doesn't change in the for loop */
#define WM_ETARETI_BAG(bag, var, i) \
for (var = WMBagLast(bag, &(i)); (i) != NULL; \
for (var = WMBagLast(bag, &(i)); (i) >= 0; \
var = WMBagPrevious(bag, &(i)))

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@@ -1,531 +0,0 @@
#include <stdlib.h>
#include <string.h>
#include "WUtil.h"
typedef struct W_Node {
struct W_Node *parent;
struct W_Node *left;
struct W_Node *right;
int color;
void *data;
int index;
} W_Node;
typedef struct W_Bag {
W_Node *root;
W_Node *nil; /* sentinel */
int count;
} W_Bag;
#define IS_LEFT(node) (node == node->parent->left)
#define IS_RIGHT(node) (node == node->parent->right)
static void leftRotate(W_Bag * tree, W_Node * node)
{
W_Node *node2;
node2 = node->right;
node->right = node2->left;
node2->left->parent = node;
node2->parent = node->parent;
if (node->parent == tree->nil) {
tree->root = node2;
} else {
if (IS_LEFT(node)) {
node->parent->left = node2;
} else {
node->parent->right = node2;
}
}
node2->left = node;
node->parent = node2;
}
static void rightRotate(W_Bag * tree, W_Node * node)
{
W_Node *node2;
node2 = node->left;
node->left = node2->right;
node2->right->parent = node;
node2->parent = node->parent;
if (node->parent == tree->nil) {
tree->root = node2;
} else {
if (IS_LEFT(node)) {
node->parent->left = node2;
} else {
node->parent->right = node2;
}
}
node2->right = node;
node->parent = node2;
}
static void treeInsert(W_Bag * tree, W_Node * node)
{
W_Node *y = tree->nil;
W_Node *x = tree->root;
while (x != tree->nil) {
y = x;
if (node->index <= x->index)
x = x->left;
else
x = x->right;
}
node->parent = y;
if (y == tree->nil)
tree->root = node;
else if (node->index <= y->index)
y->left = node;
else
y->right = node;
}
static void rbTreeInsert(W_Bag * tree, W_Node * node)
{
W_Node *y;
treeInsert(tree, node);
node->color = 'R';
while (node != tree->root && node->parent->color == 'R') {
if (IS_LEFT(node->parent)) {
y = node->parent->parent->right;
if (y->color == 'R') {
node->parent->color = 'B';
y->color = 'B';
node->parent->parent->color = 'R';
node = node->parent->parent;
} else {
if (IS_RIGHT(node)) {
node = node->parent;
leftRotate(tree, node);
}
node->parent->color = 'B';
node->parent->parent->color = 'R';
rightRotate(tree, node->parent->parent);
}
} else {
y = node->parent->parent->left;
if (y->color == 'R') {
node->parent->color = 'B';
y->color = 'B';
node->parent->parent->color = 'R';
node = node->parent->parent;
} else {
if (IS_LEFT(node)) {
node = node->parent;
rightRotate(tree, node);
}
node->parent->color = 'B';
node->parent->parent->color = 'R';
leftRotate(tree, node->parent->parent);
}
}
}
tree->root->color = 'B';
}
static void rbDeleteFixup(W_Bag * tree, W_Node * node)
{
W_Node *w;
while (node != tree->root && node->color == 'B') {
if (IS_LEFT(node)) {
w = node->parent->right;
if (w->color == 'R') {
w->color = 'B';
node->parent->color = 'R';
leftRotate(tree, node->parent);
w = node->parent->right;
}
if (w->left->color == 'B' && w->right->color == 'B') {
w->color = 'R';
node = node->parent;
} else {
if (w->right->color == 'B') {
w->left->color = 'B';
w->color = 'R';
rightRotate(tree, w);
w = node->parent->right;
}
w->color = node->parent->color;
node->parent->color = 'B';
w->right->color = 'B';
leftRotate(tree, node->parent);
node = tree->root;
}
} else {
w = node->parent->left;
if (w->color == 'R') {
w->color = 'B';
node->parent->color = 'R';
rightRotate(tree, node->parent);
w = node->parent->left;
}
if (w->left->color == 'B' && w->right->color == 'B') {
w->color = 'R';
node = node->parent;
} else {
if (w->left->color == 'B') {
w->right->color = 'B';
w->color = 'R';
leftRotate(tree, w);
w = node->parent->left;
}
w->color = node->parent->color;
node->parent->color = 'B';
w->left->color = 'B';
rightRotate(tree, node->parent);
node = tree->root;
}
}
}
node->color = 'B';
}
static W_Node *treeMinimum(W_Node * node, W_Node * nil)
{
while (node->left != nil)
node = node->left;
return node;
}
static W_Node *treeMaximum(W_Node * node, W_Node * nil)
{
while (node->right != nil)
node = node->right;
return node;
}
static W_Node *treeSuccessor(W_Node * node, W_Node * nil)
{
W_Node *y;
if (node->right != nil) {
return treeMinimum(node->right, nil);
}
y = node->parent;
while (y != nil && node == y->right) {
node = y;
y = y->parent;
}
return y;
}
static W_Node *treePredecessor(W_Node * node, W_Node * nil)
{
W_Node *y;
if (node->left != nil) {
return treeMaximum(node->left, nil);
}
y = node->parent;
while (y != nil && node == y->left) {
node = y;
y = y->parent;
}
return y;
}
static W_Node *rbTreeDelete(W_Bag * tree, W_Node * node)
{
W_Node *nil = tree->nil;
W_Node *x, *y;
if (node->left == nil || node->right == nil) {
y = node;
} else {
y = treeSuccessor(node, nil);
}
if (y->left != nil) {
x = y->left;
} else {
x = y->right;
}
x->parent = y->parent;
if (y->parent == nil) {
tree->root = x;
} else {
if (IS_LEFT(y)) {
y->parent->left = x;
} else {
y->parent->right = x;
}
}
if (y != node) {
node->index = y->index;
node->data = y->data;
}
if (y->color == 'B') {
rbDeleteFixup(tree, x);
}
return y;
}
static W_Node *treeSearch(W_Node * root, W_Node * nil, int index)
{
if (root == nil || root->index == index) {
return root;
}
if (index < root->index) {
return treeSearch(root->left, nil, index);
} else {
return treeSearch(root->right, nil, index);
}
}
static W_Node *treeFind(W_Node * root, W_Node * nil, void *data)
{
W_Node *tmp;
if (root == nil || root->data == data)
return root;
tmp = treeFind(root->left, nil, data);
if (tmp != nil)
return tmp;
tmp = treeFind(root->right, nil, data);
return tmp;
}
#if 0
static char buf[512];
static void printNodes(W_Node * node, W_Node * nil, int depth)
{
if (node == nil) {
return;
}
printNodes(node->left, nil, depth + 1);
memset(buf, ' ', depth * 2);
buf[depth * 2] = 0;
if (IS_LEFT(node))
printf("%s/(%2i\n", buf, node->index);
else
printf("%s\\(%2i\n", buf, node->index);
printNodes(node->right, nil, depth + 1);
}
void PrintTree(WMBag * bag)
{
W_TreeBag *tree = (W_TreeBag *) bag->data;
printNodes(tree->root, tree->nil, 0);
}
#endif
WMBag *WMCreateTreeBag(void)
{
WMBag *bag;
bag = wmalloc(sizeof(WMBag));
bag->nil = wmalloc(sizeof(W_Node));
bag->nil->left = bag->nil->right = bag->nil->parent = bag->nil;
bag->nil->index = WBNotFound;
bag->root = bag->nil;
return bag;
}
static int treeDeleteNode(WMBag * self, W_Node *ptr)
{
if (ptr != self->nil) {
W_Node *tmp;
self->count--;
tmp = treeSuccessor(ptr, self->nil);
while (tmp != self->nil) {
tmp->index--;
tmp = treeSuccessor(tmp, self->nil);
}
ptr = rbTreeDelete(self, ptr);
wfree(ptr);
return 1;
}
return 0;
}
void *WMGetFromBag(WMBag * self, int index)
{
W_Node *node;
node = treeSearch(self->root, self->nil, index);
if (node != self->nil)
return node->data;
else
return NULL;
}
void *WMReplaceInBag(WMBag * self, int index, void *item)
{
W_Node *ptr = treeSearch(self->root, self->nil, index);
void *old = NULL;
if (item == NULL) {
self->count--;
ptr = rbTreeDelete(self, ptr);
wfree(ptr);
} else if (ptr != self->nil) {
old = ptr->data;
ptr->data = item;
} else {
W_Node *ptr;
ptr = wmalloc(sizeof(W_Node));
ptr->data = item;
ptr->index = index;
ptr->left = self->nil;
ptr->right = self->nil;
ptr->parent = self->nil;
rbTreeInsert(self, ptr);
self->count++;
}
return old;
}
static void deleteTree(WMBag * self, W_Node * node)
{
if (node == self->nil)
return;
deleteTree(self, node->left);
deleteTree(self, node->right);
wfree(node);
}
void WMEmptyBag(WMBag * self)
{
deleteTree(self, self->root);
self->root = self->nil;
self->count = 0;
}
void WMFreeBag(WMBag * self)
{
WMEmptyBag(self);
wfree(self->nil);
wfree(self);
}
void *WMBagFirst(WMBag * self, WMBagIterator * ptr)
{
W_Node *node;
node = treeMinimum(self->root, self->nil);
if (node == self->nil) {
*ptr = NULL;
return NULL;
} else {
*ptr = node;
return node->data;
}
}
void *WMBagLast(WMBag * self, WMBagIterator * ptr)
{
W_Node *node;
node = treeMaximum(self->root, self->nil);
if (node == self->nil) {
*ptr = NULL;
return NULL;
} else {
*ptr = node;
return node->data;
}
}
void *WMBagNext(WMBag * self, WMBagIterator * ptr)
{
W_Node *node;
if (*ptr == NULL)
return NULL;
node = treeSuccessor(*ptr, self->nil);
if (node == self->nil) {
*ptr = NULL;
return NULL;
} else {
*ptr = node;
return node->data;
}
}
void *WMBagPrevious(WMBag * self, WMBagIterator * ptr)
{
W_Node *node;
if (*ptr == NULL)
return NULL;
node = treePredecessor(*ptr, self->nil);
if (node == self->nil) {
*ptr = NULL;
return NULL;
} else {
*ptr = node;
return node->data;
}
}
void *WMBagIteratorAtIndex(WMBag * self, int index, WMBagIterator * ptr)
{
W_Node *node;
node = treeSearch(self->root, self->nil, index);
if (node == self->nil) {
*ptr = NULL;
return NULL;
} else {
*ptr = node;
return node->data;
}
}

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@@ -109,16 +109,16 @@ void Shutdown(WShutdownMode mode)
}
}
static void restoreWindows(WMBag * bag, WMBagIterator iter)
static void restoreWindows(WMBag * bag, WMBagIterator *iter)
{
WCoreWindow *next;
WCoreWindow *core;
WWindow *wwin;
if (iter == NULL) {
core = WMBagFirst(bag, &iter);
if (*iter < 0) {
core = WMBagFirst(bag, iter);
} else {
core = WMBagNext(bag, &iter);
core = WMBagNext(bag, iter);
}
if (core == NULL)
@@ -168,7 +168,8 @@ void RestoreDesktop(WScreen * scr)
wDestroyInspectorPanels();
/* reparent windows back to the root window, keeping the stacking order */
restoreWindows(scr->stacking_list, NULL);
WMBagIterator iter = -1;
restoreWindows(scr->stacking_list, &iter);
XUngrabServer(dpy);
XSetInputFocus(dpy, PointerRoot, RevertToParent, CurrentTime);

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@@ -2,6 +2,7 @@ AUTOMAKE_OPTIONS =
RUST_SOURCES = \
src/array.rs \
src/bag.rs \
src/data.rs \
src/defines.c \
src/defines.rs \

390
wutil-rs/src/bag.rs Normal file
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@@ -0,0 +1,390 @@
//! Simple sorted set.
//!
//! ## Rust rewrite notes
//!
//! This was originally a full-blown red-black tree, but it was really only used
//! to keep a sorted list. It has been rewritten as a sorted `Vec`. We
//! technically no longer have O(log(n)) insertion time. Given set sizes and
//! actual execution time, that shouldn't matter.
//!
//! Prefer a proper Rust collection over this for new code.
use std::{
ffi::{c_int, c_void},
ptr::NonNull,
};
#[derive(Default)]
pub struct Bag {
inner: Vec<(c_int, NonNull<c_void>)>,
}
/// Sentinel iterator value. In C, just check for negative values.
pub const NOT_FOUND: c_int = -1;
impl Bag {
/// Returns `Ok(index)` if an item keyed by `key` is in `self`, else
/// `Err(index)` if an item keyed by `key` could be inserted at `index`.
fn search(&self, key: c_int) -> Result<usize, usize> {
// self.inner.binary_search_by(|x| key.cmp(&x.0))
self.inner.binary_search_by_key(&key, |(key, _)| *key)
}
/// Returns the index of `self.inner` where `key` is found.
fn find_index(&self, key: c_int) -> Option<usize> {
self.search(key).ok()
}
/// Returns the value associated with `key`.
fn find_value(&self, key: c_int) -> Option<NonNull<c_void>> {
let i = self.find_index(key)?;
self.inner.get(i).copied().map(|(_, value)| value)
}
/// Removes any value associated with `key`.
fn remove(&mut self, key: c_int) {
let Some(i) = self.find_index(key) else {
return;
};
self.inner.remove(i);
}
/// Sets a value associated with `key` to `value`. Clobbers any extant value.
fn set(&mut self, key: c_int, value: NonNull<c_void>) {
match self.search(key) {
Ok(i) => self.inner[i] = (key, value),
Err(i) => self.inner.insert(i, (key, value)),
}
}
}
pub mod ffi {
use super::{Bag, NOT_FOUND};
use std::{
ffi::{c_int, c_void},
ptr::{self, NonNull},
};
/// Basic constructor. Free with [`WMFreeBag`].
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMCreateTreeBag() -> *mut Bag {
Box::leak(Box::new(Bag::default()))
}
/// Retrieves the value associated with `key`, or null.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMGetFromBag(bag: *mut Bag, key: c_int) -> *mut c_void {
if bag.is_null() {
return ptr::null_mut();
}
unsafe {
(*bag)
.find_value(key)
.map(|p| p.as_ptr())
.unwrap_or(ptr::null_mut())
}
}
/// Sets the value associated with `key` to `item`. If `item` is null,
/// removes any extant value.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMSetInBag(bag: *mut Bag, key: c_int, item: *mut c_void) {
if bag.is_null() {
return;
}
let bag = unsafe { &mut *bag };
if let Some(item) = NonNull::new(item) {
bag.set(key, item);
} else {
bag.remove(key);
return;
}
}
/// Clears the contents of `bag`.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMEmptyBag(bag: *mut Bag) {
if bag.is_null() {
return;
}
unsafe {
(*bag).inner.clear();
}
}
/// Deletes `bag`.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMFreeBag(bag: *mut Bag) {
if bag.is_null() {
return;
}
unsafe {
let _ = Box::from_raw(bag);
}
}
/// Initializes `ptr` to the first element of `bag` and returns that
/// element. Sets `ptr` to [`NOT_FOUND`] and returns null if `bag` is empty.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMBagFirst(bag: *mut Bag, ptr: *mut c_int) -> *mut c_void {
if ptr.is_null() {
return ptr::null_mut();
}
let ptr = unsafe { &mut *ptr };
if bag.is_null() {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
let bag = unsafe { &mut *bag };
if let Some((_, value)) = bag.inner.first() {
*ptr = 0;
value.as_ptr()
} else {
*ptr = NOT_FOUND;
ptr::null_mut()
}
}
/// Initializes `ptr` to the last element of `bag` and returns that
/// element. Sets `ptr` to [`NOT_FOUND`] and returns null if `bag` is empty.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMBagLast(bag: *mut Bag, ptr: *mut c_int) -> *mut c_void {
if ptr.is_null() {
return ptr::null_mut();
}
let ptr = unsafe { &mut *ptr };
if bag.is_null() {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
let bag = unsafe { &mut *bag };
if let Some((_, value)) = bag.inner.last() {
*ptr = (bag.inner.len() - 1) as c_int;
value.as_ptr()
} else {
*ptr = NOT_FOUND;
ptr::null_mut()
}
}
/// Advances `ptr` to the next element of `bag` and returns it. Sets `ptr`
/// to [`NOT_FOUND`] and returns null if `ptr` is already at the end of
/// `bag`.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMBagNext(bag: *mut Bag, ptr: *mut c_int) -> *mut c_void {
if ptr.is_null() {
return ptr::null_mut();
}
let ptr = unsafe { &mut *ptr };
if bag.is_null() {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
let bag = unsafe { &mut *bag };
if *ptr < 0 {
return ptr::null_mut();
}
*ptr += 1;
if let Some((_, value)) = bag.inner.get(*ptr as usize) {
value.as_ptr()
} else {
*ptr = NOT_FOUND;
ptr::null_mut()
}
}
/// Decrements `ptr` to the previous element of `bag` and returns it. Sets `ptr`
/// to [`NOT_FOUND`] and returns null if `ptr` is already at the beginning of
/// `bag`.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMBagPrevious(bag: *mut Bag, ptr: *mut c_int) -> *mut c_void {
if ptr.is_null() {
return ptr::null_mut();
}
let ptr = unsafe { &mut *ptr };
if bag.is_null() {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
let bag = unsafe { &mut *bag };
if *ptr <= 0 {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
*ptr -= 1;
if let Some((_, value)) = bag.inner.get(*ptr as usize) {
value.as_ptr()
} else {
*ptr = NOT_FOUND;
ptr::null_mut()
}
}
/// Sets `ptr` to the element of `bag` with `key` and returns the associated
/// value. Sets `ptr` to [`NOT_FOUND`] and returns null if there is no such
/// element.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn WMBagIteratorAtIndex(
bag: *mut Bag,
key: c_int,
ptr: *mut c_int,
) -> *mut c_void {
if ptr.is_null() {
return ptr::null_mut();
}
let ptr = unsafe { &mut *ptr };
if bag.is_null() {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
let bag = unsafe { &mut *bag };
if key < 0 {
*ptr = NOT_FOUND;
return ptr::null_mut();
}
if let Some(index) = bag.find_index(key) {
*ptr = index as c_int;
bag.inner[index].1.as_ptr()
} else {
*ptr = NOT_FOUND;
ptr::null_mut()
}
}
}
#[cfg(test)]
mod test {
use super::{ffi, Bag, NOT_FOUND};
use std::{
ffi::{c_int, c_void},
ptr::NonNull,
};
fn void_of<T>(t: &mut T) -> NonNull<c_void> {
NonNull::new(t as *mut _ as *mut c_void).unwrap()
}
#[test]
fn insert_out_of_order() {
let mut b = Bag::default();
let mut x = 3u16;
let mut y = 4u16;
let mut z = 5u16;
b.set(7, void_of(&mut z));
b.set(3, void_of(&mut y));
b.set(5, void_of(&mut x));
assert_eq!(
b.inner,
&[
(3, void_of(&mut y)),
(5, void_of(&mut x)),
(7, void_of(&mut z))
]
);
}
#[test]
fn iterate_forward() {
let mut b = Bag::default();
let mut x = 3u16;
let mut y = 4u16;
let mut z = 5u16;
b.set(7, void_of(&mut z));
b.set(3, void_of(&mut y));
b.set(5, void_of(&mut x));
let mut iterator: c_int = NOT_FOUND;
unsafe {
assert_eq!(
ffi::WMBagFirst(&mut b, &mut iterator),
void_of(&mut y).as_ptr()
);
assert_eq!(iterator, 0);
assert_eq!(
ffi::WMBagNext(&mut b, &mut iterator),
void_of(&mut x).as_ptr()
);
assert_eq!(iterator, 1);
assert_eq!(
ffi::WMBagNext(&mut b, &mut iterator),
void_of(&mut z).as_ptr()
);
assert_eq!(iterator, 2);
assert!(ffi::WMBagNext(&mut b, &mut iterator).is_null());
assert_eq!(iterator, NOT_FOUND);
}
}
#[test]
fn iterate_backward() {
let mut b = Bag::default();
let mut x = 3u16;
let mut y = 4u16;
let mut z = 5u16;
b.set(7, void_of(&mut z));
b.set(3, void_of(&mut y));
b.set(5, void_of(&mut x));
let mut iterator: c_int = NOT_FOUND;
unsafe {
assert_eq!(
ffi::WMBagLast(&mut b, &mut iterator),
void_of(&mut z).as_ptr()
);
assert_eq!(iterator, 2);
assert_eq!(
ffi::WMBagPrevious(&mut b, &mut iterator),
void_of(&mut x).as_ptr()
);
assert_eq!(iterator, 1);
assert_eq!(
ffi::WMBagPrevious(&mut b, &mut iterator),
void_of(&mut y).as_ptr()
);
assert_eq!(iterator, 0);
assert!(ffi::WMBagPrevious(&mut b, &mut iterator).is_null());
assert_eq!(iterator, NOT_FOUND);
}
}
#[test]
fn find_iterate() {
let mut b = Bag::default();
let mut x = 3u16;
let mut y = 4u16;
let mut z = 5u16;
b.set(7, void_of(&mut z));
b.set(3, void_of(&mut y));
b.set(5, void_of(&mut x));
let mut iterator: c_int = NOT_FOUND;
unsafe {
assert_eq!(
ffi::WMBagIteratorAtIndex(&mut b, 5, &mut iterator),
void_of(&mut x).as_ptr()
);
assert_eq!(iterator, 1);
assert_eq!(
ffi::WMBagNext(&mut b, &mut iterator),
void_of(&mut z).as_ptr()
);
assert_eq!(iterator, 2);
}
}
}

View File

@@ -1,4 +1,5 @@
pub mod array;
pub mod bag;
pub mod data;
pub mod defines;
pub mod find_file;