Fix generational box in release mode

packages/hooks/src/lib.rs

@@ -70,6 +70,9 @@ pub use use_future::*;
 mod use_sorted;
 pub use use_sorted::*;
 
+mod use_resource;
+pub use use_resource::*;
+
 // mod use_on_create;
 // pub use use_on_create::*;
 

packages/hooks/src/use_future.rs

@@ -15,11 +15,7 @@ use std::{any::Any, cell::Cell, future::Future, pin::Pin, rc::Rc, sync::Arc, tas
 /// This is commonly used for components that cannot be rendered until some
 /// asynchronous operation has completed.
 ///
-/// Whenever the hooks dependencies change, the future will be re-evaluated.
-/// If a future is pending when the dependencies change, the previous future
-/// will be canceled before the new one is started.
 ///
-/// - dependencies: a tuple of references to values that are PartialEq + Clone
 pub fn use_future<T, F>(mut future: impl FnMut() -> F) -> UseFuture<T>
 where
     T: 'static,

packages/hooks/src/use_resource.rs

@@ -0,0 +1,127 @@
+#![allow(missing_docs)]
+use dioxus_core::{
+    prelude::{spawn, use_hook},
+    ScopeState, Task,
+};
+use dioxus_signals::{use_effect, use_signal, Effect, Signal};
+use futures_util::{future, pin_mut, FutureExt};
+use std::{any::Any, cell::Cell, future::Future, pin::Pin, rc::Rc, sync::Arc, task::Poll};
+
+/// A future that resolves to a value.
+///
+/// This runs the future only once - though the future may be regenerated
+/// through the [`UseFuture::restart`] method.
+///
+/// This is commonly used for components that cannot be rendered until some
+/// asynchronous operation has completed.
+///
+/// Whenever the hooks dependencies change, the future will be re-evaluated.
+/// If a future is pending when the dependencies change, the previous future
+/// will be canceled before the new one is started.
+///
+/// - dependencies: a tuple of references to values that are PartialEq + Clone
+pub fn use_resource<T, F>(future: impl Fn() -> F) -> UseResource<T>
+where
+    T: 'static,
+    F: Future<Output = T> + 'static,
+{
+    let mut value = use_signal(|| None);
+    let mut state = use_signal(|| UseResourceState::Pending);
+
+    let task = use_signal(|| {
+        // Create the user's task
+        let fut = future();
+
+        // Spawn a wrapper task that polls the innner future and watch its dependencies
+        let task = spawn(async move {
+            // move the future here and pin it so we can poll it
+            let fut = fut;
+            pin_mut!(fut);
+
+            let res = future::poll_fn(|cx| {
+                // Set the effect stack properly
+
+                // Poll the inner future
+                let ready = fut.poll_unpin(cx);
+
+                // add any dependencies to the effect stack that we need to watch when restarting the future
+
+                ready
+            })
+            .await;
+
+            // Set the value
+            value.set(Some(res));
+        });
+
+        Some(task)
+    });
+
+    UseResource { task, value, state }
+}
+
+pub struct UseResource<T: 'static> {
+    value: Signal<Option<T>>,
+    task: Signal<Option<Task>>,
+    state: Signal<UseResourceState<T>>,
+}
+
+impl<T> UseResource<T> {
+    /// Restart the future with new dependencies.
+    ///
+    /// Will not cancel the previous future, but will ignore any values that it
+    /// generates.
+    pub fn restart(&self) {
+        // self.needs_regen.set(true);
+        // (self.update)();
+    }
+
+    /// Forcefully cancel a future
+    pub fn cancel(&self) {
+        // if let Some(task) = self.task.take() {
+        //     cx.remove_future(task);
+        // }
+    }
+
+    // Manually set the value in the future slot without starting the future over
+    pub fn set(&mut self, new_value: T) {
+        self.value.set(Some(new_value));
+    }
+
+    /// Return any value, even old values if the future has not yet resolved.
+    ///
+    /// If the future has never completed, the returned value will be `None`.
+    pub fn value(&self) -> Signal<Option<T>> {
+        self.value
+    }
+
+    /// Get the ID of the future in Dioxus' internal scheduler
+    pub fn task(&self) -> Option<Task> {
+        todo!()
+        // self.task.get()
+    }
+
+    /// Get the current state of the future.
+    pub fn state(&self) -> UseResourceState<T> {
+        todo!()
+        // match (&self.task.get(), &self.value()) {
+        //     // If we have a task and an existing value, we're reloading
+        //     (Some(_), Some(val)) => UseResourceState::Reloading(val),
+
+        //     // no task, but value - we're done
+        //     (None, Some(val)) => UseResourceState::Complete(val),
+
+        //     // no task, no value - something's wrong? return pending
+        //     (None, None) => UseResourceState::Pending,
+
+        //     // Task, no value - we're still pending
+        //     (Some(_), None) => UseResourceState::Pending,
+        // }
+    }
+}
+
+pub enum UseResourceState<T: 'static> {
+    Pending,
+    Complete(Signal<T>),
+    Regenerating(Signal<T>), // the old value
+}