make ResourceId newtype instead of typedef

src/poller/popol.rs

@@ -50,7 +50,7 @@ impl Poller {
         Self {
             poll: popol::Sources::new(),
             events: empty!(),
-            id_top: 0,
+            id_top: ResourceId::ZERO,
         }
     }
 
@@ -60,7 +60,7 @@ impl Poller {
         Self {
             poll: popol::Sources::with_capacity(capacity),
             events: VecDeque::with_capacity(capacity),
-            id_top: 0,
+            id_top: ResourceId::ZERO,
         }
     }
 }
@@ -70,7 +70,7 @@ impl Poll for Poller {
 
     fn register(&mut self, fd: &impl AsRawFd, interest: IoType) -> ResourceId {
         let id = self.id_top;
-        self.id_top += 1;
+        self.id_top.inc();
 
         #[cfg(feature = "log")]
         log::trace!(target: "popol", "Registering file descriptor {} as resource with id {}", fd.as_raw_fd(), id);

src/resource.rs

@@ -40,7 +40,15 @@ pub enum Io {
 
 /// The resource identifier must be globally unique and non-reusable object. Because of this,
 /// things like [`RawFd`] and socket addresses can't operate like resource identifiers.
-pub type ResourceId = u64;
+#[derive(Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Hash, Debug, Display)]
+#[display(inner)]
+pub struct ResourceId(u64);
+
+impl ResourceId {
+    pub(crate) const ZERO: ResourceId = ResourceId(0);
+
+    pub(crate) fn inc(&mut self) { self.0 += 1 }
+}
 
 /// A resource which can be managed by the reactor.
 pub trait Resource: AsRawFd + WriteAtomic + Send {