Repository: tokio-rs/tokio
File: tokio/src/net/tcp/stream.rs (Rust)

Code before:
        f: impl FnOnce() -> io::Result<R>,
    ) -> io::Result<R> {
        self.io
            .registration()
            .try_io(interest, || self.io.try_io(f))
    }
    
    /// Reads or writes from the socket using a user-provided IO operation.
    ///
    /// The readiness of the socket is awaited and when the socket is ready,
    /// the provided closure is called. The closure should attempt to perform
    /// IO operation on the socket by manually calling the appropriate syscall.
    /// If the operation fails because the socket is not actually ready,
    /// then the closure should return a `WouldBlock` error, the readiness
    /// flag is cleared and the socket readiness is awaited again. This loop
    /// repeated until the closure returns an `Ok` or an error that doesn't
    /// have the `WouldBlock` value.
    ///
    /// The closure should only return a `WouldBlock` error if it has performed
    /// an IO operation on the socket that failed due to the socket not being
    /// ready. Returning a `WouldBlock` error in any other situation will
    /// incorrectly clear the readiness flag, which can cause the socket to
    /// behave incorrectly.
    ///
    /// The closure should not perform the IO operation using any of the methods
    /// defined on the Tokio `UdpSocket` type, as this will mess with the
    /// readiness flag and can cause the socket to behave incorrectly.
    ///
    /// This method is not intended to be used with combined interests.
    /// The closure should perform only one type of IO operation, so it should not
    /// require more than one ready state. This method may panic or sleep forever
    /// if it is called with a combined interest.
    ///
    /// Usually, [`readable()`], [`writable()`] or [`ready()`] is used with this function.
    ///
    /// [`readable()`]: UdpSocket::readable()
    /// [`writable()`]: UdpSocket::writable()
    /// [`ready()`]: UdpSocket::ready()
    pub async fn async_io<R>(
        &self, 
        interest: Interest, 
        mut f: impl FnMut() -> io::Result<R>,
    ) -> io::Result<R> {
        self.io
            .registration()
            .async_io(interest, || self.io.try_io(&mut f) )
            .await
    }

    /// Receives data on the socket from the remote address to which it is
    /// connected, without removing that data from the queue. On success,

Review comment (suggestion):
Here it should refer to the `TcpStream`, as this is the type we are adding a method for. The same goes for other types.
```suggestion
    /// defined on the Tokio `TcpStream` type, as this will mess with the
```

Code after:
        f: impl FnOnce() -> io::Result<R>,
    ) -> io::Result<R> {
        self.io
            .registration()
            .try_io(interest, || self.io.try_io(f))
    }

    /// Reads or writes from the socket using a user-provided IO operation.
    ///
    /// The readiness of the socket is awaited and when the socket is ready,
    /// the provided closure is called. The closure should attempt to perform
    /// IO operation on the socket by manually calling the appropriate syscall.
    /// If the operation fails because the socket is not actually ready,
    /// then the closure should return a `WouldBlock` error. In such case the
    /// readiness flag is cleared and the socket readiness is awaited again.
    /// This loop is repeated until the closure returns an `Ok` or an error
    /// other than `WouldBlock`.
    ///
    /// The closure should only return a `WouldBlock` error if it has performed
    /// an IO operation on the socket that failed due to the socket not being
    /// ready. Returning a `WouldBlock` error in any other situation will
    /// incorrectly clear the readiness flag, which can cause the socket to
    /// behave incorrectly.
    ///
    /// The closure should not perform the IO operation using any of the methods
    /// defined on the Tokio `TcpStream` type, as this will mess with the
    /// readiness flag and can cause the socket to behave incorrectly.
    ///
    /// This method is not intended to be used with combined interests.
    /// The closure should perform only one type of IO operation, so it should not
    /// require more than one ready state. This method may panic or sleep forever
    /// if it is called with a combined interest.
    pub async fn async_io<R>(
        &self,
        interest: Interest,
        mut f: impl FnMut() -> io::Result<R>,
    ) -> io::Result<R> {
        self.io
            .registration()
            .async_io(interest, || self.io.try_io(&mut f))
            .await
    }

    /// Receives data on the socket from the remote address to which it is
    /// connected, without removing that data from the queue. On success,
    /// returns the number of bytes peeked.
    ///
    /// Successive calls return the same data. This is accomplished by passing
    /// `MSG_PEEK` as a flag to the underlying recv system call.
    ///
    /// # Examples