Improve None/Some doc links

wayland-backend/src/client_api.rs

@@ -151,7 +151,7 @@ pub struct WeakBackend {
 impl WeakBackend {
     /// Try to upgrade this weak handle to a [`Backend`]
     ///
-    /// Returns `None` if the associated backend was already dropped.
+    /// Returns [`None`] if the associated backend was already dropped.
     pub fn upgrade(&self) -> Option<Backend> {
         self.inner.upgrade().map(|backend| Backend { backend })
     }
@@ -262,7 +262,7 @@ impl Backend {
     /// This is the first step for actually reading events from the Wayland socket. See
     /// [`ReadEventsGuard`] for how to use it.
     ///
-    /// This call will not block, but may return `None` if the inner queue of the backend needs to
+    /// This call will not block, but may return [`None`] if the inner queue of the backend needs to
     /// be dispatched. In which case you should invoke
     /// [`dispatch_inner_queue()`][Self::dispatch_inner_queue()].
     #[inline]
@@ -278,7 +278,7 @@ impl Backend {
     /// queue that the backend uses to wrap `libwayland`. While this dispatching is generally done in
     /// [`ReadEventsGuard::read()`], if multiple threads are interacting with the
     /// Wayland socket it can happen that this queue was filled by another thread. In that case
-    /// [`prepare_read()`][Self::prepare_read()] will return `None`, and you should invoke
+    /// [`prepare_read()`][Self::prepare_read()] will return [`None`], and you should invoke
     /// this function instead of using the [`ReadEventsGuard`]
     ///
     /// Returns the number of messages that were dispatched to their [`ObjectData`] callbacks.

wayland-backend/src/server_api.rs

@@ -250,7 +250,7 @@ pub struct WeakHandle {
 impl WeakHandle {
     /// Try to upgrade this weak handle to a [`Handle`]
     ///
-    /// Returns `None` if the associated backend was already dropped.
+    /// Returns [`None`] if the associated backend was already dropped.
     #[inline]
     pub fn upgrade(&self) -> Option<Handle> {
         self.handle.upgrade().map(|handle| Handle { handle })

wayland-client/src/conn.rs

@@ -177,7 +177,7 @@ impl Connection {
 
     /// Retrieve the protocol error that occured on the connection if any
     ///
-    /// If this method returns `Some`, it means your Wayland connection is already dead.
+    /// If this method returns [`Some`], it means your Wayland connection is already dead.
     pub fn protocol_error(&self) -> Option<ProtocolError> {
         match self.backend.last_error()? {
             WaylandError::Protocol(err) => Some(err),