Pinning To poll futures, they must be pinned using a special type called Pin<T>. If you read the explanation of the Future trait in the previous section "Executing Futures and Tasks", you'll recognize Pin from the self: Pin<&mut Self> in the Future::poll method's definition. But what does it mean, and why do we need it? Why Pinning Pin works in tandem with the Unpin marker. Pinning makes it possib

