Improving our example 4 – pinning to the rescue

Fortunately, the changes we need to make are small, but before we continue and make the changes, let’s create a new folder and copy everything we had in our previous example over to that folder:

• Copy the entire c-coroutines-problem folder and name the new copy e-coroutines-pin
• Open Cargo.toml and rename the name of the package e-coroutines-pin

Tip

You’ll find the example code we’ll go through here in this book’s GitHub repository under the ch09/e-coroutines-pin folder.

Now that we have a new folder set up, let’s start making the necessary changes. The logical place to start is our Future definition in future.rs.

future.rs

The first thing we’ll do is pull in Pin from the standard library at the very top:

ch09/e-coroutines-pin/src/future.rs

use std::pin::Pin;

The only other change we need to make is in the definition of poll in our Future trait:

fn...