feat: suspense!

packages/core/src/scheduler/handle.rs

@@ -0,0 +1,31 @@
+use futures_util::Future;
+use slab::Slab;
+use std::{cell::RefCell, pin::Pin, rc::Rc, sync::Arc};
+
+use super::{LocalTask, SchedulerMsg, SuspenseLeaf};
+
+#[derive(Clone)]
+pub struct SchedulerHandle(Rc<HandleInner>);
+
+impl std::ops::Deref for SchedulerHandle {
+    type Target = HandleInner;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+pub struct HandleInner {
+    pub sender: futures_channel::mpsc::UnboundedSender<SchedulerMsg>,
+    pub tasks: RefCell<Slab<LocalTask>>,
+    pub leaves: RefCell<Slab<SuspenseLeaf>>,
+}
+
+impl SchedulerHandle {
+    pub fn new(sender: futures_channel::mpsc::UnboundedSender<SchedulerMsg>) -> Self {
+        Self(Rc::new(HandleInner {
+            sender,
+            tasks: RefCell::new(Slab::new()),
+            leaves: RefCell::new(Slab::new()),
+        }))
+    }
+}