X-Git-Url: https://git.ralfj.de/rust-101.git/blobdiff_plain/4b75a1808a0ee75383f81659f6262fefc7047a09..2d40516a8393db1f27bb822ff95c71a1a9c82537:/workspace/src/part12.rs diff --git a/workspace/src/part12.rs b/workspace/src/part12.rs index 86fb4bb..1593e8a 100644 --- a/workspace/src/part12.rs +++ b/workspace/src/part12.rs @@ -46,9 +46,9 @@ pub fn main() { fn demo_cell(c: &mut Callbacks) { { let count = Cell::new(0); - // Again, we have to move ownership if the `count` into the environment closure. + // Again, we have to move ownership of the `count` into the environment closure. c.register(move |val| { - // In here, all we have is a shared borrow of our environment. But that's good enough for the `get` and `set` of the cell! + // In here, all we have is a shared reference of our environment. But that's good enough for the `get` and `set` of the cell! let new_count = count.get()+1; count.set(new_count); println!("Callback 2: {} ({}. time)", val, new_count); @@ -81,7 +81,7 @@ impl CallbacksMut { // We have to *explicitly* borrow the contents of a `RefCell` by calling `borrow` or `borrow_mut`. let mut closure = callback.borrow_mut(); // Unfortunately, Rust's auto-dereference of pointers is not clever enough here. We thus have to explicitly - // dereference the smart pointer and obtain a mutable borrow of the content. + // dereference the smart pointer and obtain a mutable reference to the content. (&mut *closure)(val); } } @@ -104,5 +104,5 @@ fn demo_mut(c: &mut CallbacksMut) { } // **Exercise 12.1**: Write some piece of code using only the available, public interface of `CallbacksMut` such that a reentrant call to a closure -// is happening, and the program aborts because the `RefCell` refuses to hand out a second mutable borrow of the closure's environment. +// is happening, and the program panics because the `RefCell` refuses to hand out a second mutable borrow of the closure's environment.