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Why does "move" in Rust not actually move?


Why does "move" in Rust not actually move?

By : Shwilly Kidd
Date : November 20 2020, 07:00 PM
To fix the issue you can do A move is a memcpy followed by treating the source as non-existent.
Your big array is on the stack. That's just the way Rust's memory model works: local variables are on the stack. Since the stack space of foo is going away when the function returns, there's nothing else the compiler can do except copy the memory to main's stack space.
code :


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Rust: "cannot move out of `self` because it is borrowed" error

Rust: "cannot move out of `self` because it is borrowed" error


By : Rodney Deadwyler
Date : March 29 2020, 07:55 AM
should help you out In your example node_item, left and right are owned by the self variable. The borrow checker doesn't know that in the Equal branch of
code :
match item.cmp(node_item) {
    Less => left.insert(item),
    Equal => self,
    Greater => right.insert(item)
}
pub struct BstNode {
  item: int,
  left: Option<~BstNode>,
  right: Option<~BstNode>
}

impl BstNode {
    pub fn insert<'a>(&'a mut self, item: int) -> &'a mut BstNode {
        match item.cmp(&self.item) {
            Less => match self.left {
              Some(ref mut lnode) => lnode.insert(item),
              None => {
                self.left = Some(~BstNode {item: item, left: None, right: None});
                &mut **self.left.as_mut().unwrap()
              }
            },
            Equal => self,
            Greater => match self.right {
              Some(ref mut rnode) => rnode.insert(item),
              None => {
                self.right = Some(~BstNode {item: item, left: None, right: None});
                &mut **self.right.as_mut().unwrap()
              }
            }
        }
    }
}
Why can I "move" a static &str into multiple threads in Rust?

Why can I "move" a static &str into multiple threads in Rust?


By : Thway
Date : March 29 2020, 07:55 AM
wish helps you
I have shared the same variable mutable between multiple threads and even mutated it.
Why is the default behavior in Rust to perform a move on assignment rather than just create another "reference"

Why is the default behavior in Rust to perform a move on assignment rather than just create another "reference"


By : user275379
Date : March 29 2020, 07:55 AM
I wish this helpful for you
[...] what is the rationale for not making them "smart references"?
Replacing values in Rust causing "cannot move out of borrowed content"

Replacing values in Rust causing "cannot move out of borrowed content"


By : 張永原
Date : March 29 2020, 07:55 AM
I wish this helpful for you
How do I tell the borrow checker that I'm not trying to alias self.next_buffer, I'm trying to move it, and put something new in its place?
code :
self.current_buffer = mem::replace(&mut self.next_buffer, Buffer { ... });
Why is iterating over a collection via `for` loop considered a "move" in Rust?

Why is iterating over a collection via `for` loop considered a "move" in Rust?


By : Nic
Date : September 25 2020, 09:00 AM
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