diff --git a/src/libcore/mem.rs b/src/libcore/mem.rs index 7e63c8d71f92832d3af3bf702ae1989009e6ce0d..86b331d220a3b30e0b55ab2d6a672e2271145a14 100644 --- a/src/libcore/mem.rs +++ b/src/libcore/mem.rs @@ -29,6 +29,19 @@ /// `mem::drop` function in that it **does not run the destructor**, leaking the /// value and any resources that it owns. /// +/// There's only a few reasons to use this function. They mainly come +/// up in unsafe code or FFI code. +/// +/// * You have an uninitialized value, perhaps for performance reasons, and +/// need to prevent the destructor from running on it. +/// * You have two copies of a value (like when writing something like +/// [`mem::swap`][swap]), but need the destructor to only run once to +/// prevent a double `free`. +/// * Transferring resources across [FFI][ffi] boundries. +/// +/// [swap]: fn.swap.html +/// [ffi]: ../../book/ffi.html +/// /// # Safety /// /// This function is not marked as `unsafe` as Rust does not guarantee that the @@ -52,20 +65,9 @@ /// * `mpsc::{Sender, Receiver}` cycles (they use `Arc` internally) /// * Panicking destructors are likely to leak local resources /// -/// # When To Use -/// -/// There's only a few reasons to use this function. They mainly come -/// up in unsafe code or FFI code. -/// -/// * You have an uninitialized value, perhaps for performance reasons, and -/// need to prevent the destructor from running on it. -/// * You have two copies of a value (like `std::mem::swap`), but need the -/// destructor to only run once to prevent a double free. -/// * Transferring resources across FFI boundries. -/// /// # Example /// -/// Leak some heap memory by never deallocating it. +/// Leak some heap memory by never deallocating it: /// /// ```rust /// use std::mem; @@ -74,7 +76,7 @@ /// mem::forget(heap_memory); /// ``` /// -/// Leak an I/O object, never closing the file. +/// Leak an I/O object, never closing the file: /// /// ```rust,no_run /// use std::mem; @@ -84,7 +86,7 @@ /// mem::forget(file); /// ``` /// -/// The swap function uses forget to good effect. +/// The `mem::swap` function uses `mem::forget` to good effect: /// /// ```rust /// use std::mem;