//@ Clearly, that's an unsafe operation and must only be used with great care - or even better, not at all. Seriously.
//@ If at all possible, you should never use `transmute`. <br/>
//@ We are making the assumption here that a `Box` and a raw pointer have the same representation in memory. In the future,
-//@ Rust will [provide](http://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#method.from_raw) such [operations](http://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#method.into_raw) in the standard library, but the exact API is still being fleshed out.
+//@ Rust will [provide](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#method.from_raw) such [operations](https://doc.rust-lang.org/beta/alloc/boxed/struct.Box.html#method.into_raw) in the standard library, but the exact API is still being fleshed out.
//@ We declare `raw_into_box` to be an `unsafe` function, telling Rust that calling this function is not generally safe.
//@ This grants us the unsafe powers for the body of the function: We can dereference raw pointers, and - most importantly - we
-//@ can call unsafe functions. (There's a third power, related to mutable static variables, but we didn't talk about static variables
-//@ in the course, so that won't be relevant here.) <br/>
+//@ can call unsafe functions. (The other unsafe powers won't be relevant here. Go read [The Rustonomicon](https://doc.rust-lang.org/nightly/nomicon/)
+//@ if you want to learn all about this, but be warned - That Way Lies Madness.) <br/>
//@ Here, the caller will have to ensure that `r` is a valid pointer, and that nobody else has a pointer to this data.
unsafe fn raw_into_box<T>(r: *mut T) -> Box<T> {
mem::transmute(r)
//@ Calling `box_into_raw` gives up ownership of the box, which is crucial: We don't want the memory that it points to to be deallocated!
let new = Box::new( Node { data: t, next: ptr::null_mut(), prev: self.last } );
let new = box_into_raw(new);
- // Update other points to this node.
+ // Update other pointers to this node.
if self.last.is_null() {
debug_assert!(self.first.is_null());
// The list is currently empty, so we have to update the head pointer.
// Next, we are going to provide an iterator.
//@ This function just creates an instance of `IterMut`, the iterator type which does the actual work.
- pub fn iter_mut(&self) -> IterMut<T> {
+ pub fn iter_mut(&mut self) -> IterMut<T> {
IterMut { next: self.first, _marker: PhantomData }
}
}
//@ of `LinkedList`.
impl<T> Drop for LinkedList<T> {
// The destructor itself is a method which takes `self` in mutably borrowed form. It cannot own `self`, because then
- // the destructor of `self` would be called at the end pf the function, resulting in endless recursion...
+ // the destructor of `self` would be called at the end of the function, resulting in endless recursion...
fn drop(&mut self) {
let mut cur_ptr = self.first;
while !cur_ptr.is_null() {
//@ extensions here and there. The [index](main.html) contains some more links to additional resources you may find useful.
//@ With that, there's only one thing left to say: Happy Rust Hacking!
-//@ [index](main.html) | [previous](part15.html) | next
+//@ [index](main.html) | [previous](part15.html) | [raw source](https://www.ralfj.de/git/rust-101.git/blob_plain/HEAD:/workspace/src/part16.rs) | next