feat: resupport From<Fn() -> T> for Signal<T>, ArcSignal<T>, Callback<T, _> and similar (#4273)

reactive_graph/Cargo.toml

@@ -29,6 +29,7 @@ send_wrapper = { features = [
 ], workspace = true, default-features = true }
 subsecond = { workspace = true, default-features = true, optional = true }
 indexmap = { workspace = true, default-features = true }
+paste = { workspace = true, default-features = true }
 
 [target.'cfg(all(target_arch = "wasm32", target_os = "unknown"))'.dependencies]
 web-sys = { version = "0.3.77", features = ["console"] }
@@ -40,6 +41,7 @@ tokio = { features = [
 ], workspace = true, default-features = true }
 tokio-test = { workspace = true, default-features = true }
 any_spawner = { workspace = true, features = ["futures-executor", "tokio"] }
+typed-builder.workspace = true
 
 [build-dependencies]
 rustc_version = { workspace = true, default-features = true }

reactive_graph/src/callback.rs

@@ -0,0 +1,417 @@
+//! Callbacks define a standard way to store functions and closures. They are useful
+//! for component properties, because they can be used to define optional callback functions,
+//! which generic props don’t support.
+//!
+//! The callback types implement [`Copy`], so they can easily be moved into and out of other closures, just like signals.
+//!
+//! # Types
+//! This modules implements 2 callback types:
+//! - [`Callback`](reactive_graph::callback::Callback)
+//! - [`UnsyncCallback`](reactive_graph::callback::UnsyncCallback)
+//!
+//! Use `SyncCallback` if the function is not `Sync` and `Send`.
+
+use crate::{
+    owner::{LocalStorage, StoredValue},
+    traits::{Dispose, WithValue},
+    IntoReactiveValue,
+};
+use std::{fmt, rc::Rc, sync::Arc};
+
+/// A wrapper trait for calling callbacks.
+pub trait Callable<In: 'static, Out: 'static = ()> {
+    /// calls the callback with the specified argument.
+    ///
+    /// Returns None if the callback has been disposed
+    fn try_run(&self, input: In) -> Option<Out>;
+    /// calls the callback with the specified argument.
+    ///
+    /// # Panics
+    /// Panics if you try to run a callback that has been disposed
+    fn run(&self, input: In) -> Out;
+}
+
+/// A callback type that is not required to be [`Send`] or [`Sync`].
+///
+/// # Example
+/// ```
+/// # use reactive_graph::prelude::*; use reactive_graph::callback::*;  let owner = reactive_graph::owner::Owner::new(); owner.set();
+/// let _: UnsyncCallback<()> = UnsyncCallback::new(|_| {});
+/// let _: UnsyncCallback<(i32, i32)> = (|_x: i32, _y: i32| {}).into();
+/// let cb: UnsyncCallback<i32, String> = UnsyncCallback::new(|x: i32| x.to_string());
+/// assert_eq!(cb.run(42), "42".to_string());
+/// ```
+pub struct UnsyncCallback<In: 'static, Out: 'static = ()>(
+    StoredValue<Rc<dyn Fn(In) -> Out>, LocalStorage>,
+);
+
+impl<In> fmt::Debug for UnsyncCallback<In> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        fmt.write_str("Callback")
+    }
+}
+
+impl<In, Out> Copy for UnsyncCallback<In, Out> {}
+
+impl<In, Out> Clone for UnsyncCallback<In, Out> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<In, Out> Dispose for UnsyncCallback<In, Out> {
+    fn dispose(self) {
+        self.0.dispose();
+    }
+}
+
+impl<In, Out> UnsyncCallback<In, Out> {
+    /// Creates a new callback from the given function.
+    pub fn new<F>(f: F) -> UnsyncCallback<In, Out>
+    where
+        F: Fn(In) -> Out + 'static,
+    {
+        Self(StoredValue::new_local(Rc::new(f)))
+    }
+
+    /// Returns `true` if both callbacks wrap the same underlying function pointer.
+    #[inline]
+    pub fn matches(&self, other: &Self) -> bool {
+        self.0.with_value(|self_value| {
+            other
+                .0
+                .with_value(|other_value| Rc::ptr_eq(self_value, other_value))
+        })
+    }
+}
+
+impl<In: 'static, Out: 'static> Callable<In, Out> for UnsyncCallback<In, Out> {
+    fn try_run(&self, input: In) -> Option<Out> {
+        self.0.try_with_value(|fun| fun(input))
+    }
+
+    fn run(&self, input: In) -> Out {
+        self.0.with_value(|fun| fun(input))
+    }
+}
+
+macro_rules! impl_unsync_callable_from_fn {
+    ($($arg:ident),*) => {
+        impl<F, $($arg,)* T, Out> From<F> for UnsyncCallback<($($arg,)*), Out>
+        where
+            F: Fn($($arg),*) -> T + 'static,
+            T: Into<Out> + 'static,
+            $($arg: 'static,)*
+        {
+            fn from(f: F) -> Self {
+                paste::paste!(
+                    Self::new(move |($([<$arg:lower>],)*)| f($([<$arg:lower>]),*).into())
+                )
+            }
+        }
+    };
+}
+
+impl_unsync_callable_from_fn!();
+impl_unsync_callable_from_fn!(P1);
+impl_unsync_callable_from_fn!(P1, P2);
+impl_unsync_callable_from_fn!(P1, P2, P3);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9, P10);
+impl_unsync_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11);
+impl_unsync_callable_from_fn!(
+    P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12
+);
+
+/// A callback type that is [`Send`] + [`Sync`].
+///
+/// # Example
+/// ```
+/// # use reactive_graph::prelude::*; use reactive_graph::callback::*;  let owner = reactive_graph::owner::Owner::new(); owner.set();
+/// let _: Callback<()> = Callback::new(|_| {});
+/// let _: Callback<(i32, i32)> = (|_x: i32, _y: i32| {}).into();
+/// let cb: Callback<i32, String> = Callback::new(|x: i32| x.to_string());
+/// assert_eq!(cb.run(42), "42".to_string());
+/// ```
+pub struct Callback<In, Out = ()>(
+    StoredValue<Arc<dyn Fn(In) -> Out + Send + Sync>>,
+)
+where
+    In: 'static,
+    Out: 'static;
+
+impl<In, Out> fmt::Debug for Callback<In, Out> {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
+        fmt.write_str("SyncCallback")
+    }
+}
+
+impl<In, Out> Callable<In, Out> for Callback<In, Out> {
+    fn try_run(&self, input: In) -> Option<Out> {
+        self.0.try_with_value(|fun| fun(input))
+    }
+
+    fn run(&self, input: In) -> Out {
+        self.0.with_value(|f| f(input))
+    }
+}
+
+impl<In, Out> Clone for Callback<In, Out> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<In, Out> Dispose for Callback<In, Out> {
+    fn dispose(self) {
+        self.0.dispose();
+    }
+}
+
+impl<In, Out> Copy for Callback<In, Out> {}
+
+macro_rules! impl_callable_from_fn {
+    ($($arg:ident),*) => {
+        impl<F, $($arg,)* T, Out> From<F> for Callback<($($arg,)*), Out>
+        where
+            F: Fn($($arg),*) -> T + Send + Sync + 'static,
+            T: Into<Out> + 'static,
+            $($arg: Send + Sync + 'static,)*
+        {
+            fn from(f: F) -> Self {
+                paste::paste!(
+                    Self::new(move |($([<$arg:lower>],)*)| f($([<$arg:lower>]),*).into())
+                )
+            }
+        }
+    };
+}
+
+impl_callable_from_fn!();
+impl_callable_from_fn!(P1);
+impl_callable_from_fn!(P1, P2);
+impl_callable_from_fn!(P1, P2, P3);
+impl_callable_from_fn!(P1, P2, P3, P4);
+impl_callable_from_fn!(P1, P2, P3, P4, P5);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9, P10);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11);
+impl_callable_from_fn!(P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P11, P12);
+
+impl<In: 'static, Out: 'static> Callback<In, Out> {
+    /// Creates a new callback from the given function.
+    #[track_caller]
+    pub fn new<F>(fun: F) -> Self
+    where
+        F: Fn(In) -> Out + Send + Sync + 'static,
+    {
+        Self(StoredValue::new(Arc::new(fun)))
+    }
+
+    /// Returns `true` if both callbacks wrap the same underlying function pointer.
+    #[inline]
+    pub fn matches(&self, other: &Self) -> bool {
+        self.0
+            .try_with_value(|self_value| {
+                other.0.try_with_value(|other_value| {
+                    Arc::ptr_eq(self_value, other_value)
+                })
+            })
+            .flatten()
+            .unwrap_or(false)
+    }
+}
+
+#[doc(hidden)]
+pub struct __IntoReactiveValueMarkerCallbackSingleParam;
+
+#[doc(hidden)]
+pub struct __IntoReactiveValueMarkerCallbackStrOutputToString;
+
+impl<I, O, F>
+    IntoReactiveValue<
+        Callback<I, O>,
+        __IntoReactiveValueMarkerCallbackSingleParam,
+    > for F
+where
+    F: Fn(I) -> O + Send + Sync + 'static,
+{
+    #[track_caller]
+    fn into_reactive_value(self) -> Callback<I, O> {
+        Callback::new(self)
+    }
+}
+
+impl<I, O, F>
+    IntoReactiveValue<
+        UnsyncCallback<I, O>,
+        __IntoReactiveValueMarkerCallbackSingleParam,
+    > for F
+where
+    F: Fn(I) -> O + 'static,
+{
+    #[track_caller]
+    fn into_reactive_value(self) -> UnsyncCallback<I, O> {
+        UnsyncCallback::new(self)
+    }
+}
+
+impl<I, F>
+    IntoReactiveValue<
+        Callback<I, String>,
+        __IntoReactiveValueMarkerCallbackStrOutputToString,
+    > for F
+where
+    F: Fn(I) -> &'static str + Send + Sync + 'static,
+{
+    #[track_caller]
+    fn into_reactive_value(self) -> Callback<I, String> {
+        Callback::new(move |i| self(i).to_string())
+    }
+}
+
+impl<I, F>
+    IntoReactiveValue<
+        UnsyncCallback<I, String>,
+        __IntoReactiveValueMarkerCallbackStrOutputToString,
+    > for F
+where
+    F: Fn(I) -> &'static str + 'static,
+{
+    #[track_caller]
+    fn into_reactive_value(self) -> UnsyncCallback<I, String> {
+        UnsyncCallback::new(move |i| self(i).to_string())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Callable;
+    use crate::{
+        callback::{Callback, UnsyncCallback},
+        owner::Owner,
+        traits::Dispose,
+        IntoReactiveValue,
+    };
+
+    struct NoClone {}
+
+    #[test]
+    fn clone_callback() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback = Callback::new(move |_no_clone: NoClone| NoClone {});
+        let _cloned = callback;
+    }
+
+    #[test]
+    fn clone_unsync_callback() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback =
+            UnsyncCallback::new(move |_no_clone: NoClone| NoClone {});
+        let _cloned = callback;
+    }
+
+    #[test]
+    fn runback_from() {
+        let owner = Owner::new();
+        owner.set();
+
+        let _callback: Callback<(), String> = (|| "test").into();
+        let _callback: Callback<(i32, String), String> =
+            (|num, s| format!("{num} {s}")).into();
+        // Single params should work without needing the (foo,) tuple using IntoReactiveValue:
+        let _callback: Callback<usize, &'static str> =
+            (|_usize| "test").into_reactive_value();
+        let _callback: Callback<usize, String> =
+            (|_usize| "test").into_reactive_value();
+    }
+
+    #[test]
+    fn sync_callback_from() {
+        let owner = Owner::new();
+        owner.set();
+
+        let _callback: UnsyncCallback<(), String> = (|| "test").into();
+        let _callback: UnsyncCallback<(i32, String), String> =
+            (|num, s| format!("{num} {s}")).into();
+        // Single params should work without needing the (foo,) tuple using IntoReactiveValue:
+        let _callback: UnsyncCallback<usize, &'static str> =
+            (|_usize| "test").into_reactive_value();
+        let _callback: UnsyncCallback<usize, String> =
+            (|_usize| "test").into_reactive_value();
+    }
+
+    #[test]
+    fn sync_callback_try_run() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback = Callback::new(move |arg| arg);
+        assert_eq!(callback.try_run((0,)), Some((0,)));
+        callback.dispose();
+        assert_eq!(callback.try_run((0,)), None);
+    }
+
+    #[test]
+    fn unsync_callback_try_run() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback = UnsyncCallback::new(move |arg| arg);
+        assert_eq!(callback.try_run((0,)), Some((0,)));
+        callback.dispose();
+        assert_eq!(callback.try_run((0,)), None);
+    }
+
+    #[test]
+    fn callback_matches_same() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback1 = Callback::new(|x: i32| x * 2);
+        let callback2 = callback1;
+        assert!(callback1.matches(&callback2));
+    }
+
+    #[test]
+    fn callback_matches_different() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback1 = Callback::new(|x: i32| x * 2);
+        let callback2 = Callback::new(|x: i32| x + 1);
+        assert!(!callback1.matches(&callback2));
+    }
+
+    #[test]
+    fn unsync_callback_matches_same() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback1 = UnsyncCallback::new(|x: i32| x * 2);
+        let callback2 = callback1;
+        assert!(callback1.matches(&callback2));
+    }
+
+    #[test]
+    fn unsync_callback_matches_different() {
+        let owner = Owner::new();
+        owner.set();
+
+        let callback1 = UnsyncCallback::new(|x: i32| x * 2);
+        let callback2 = UnsyncCallback::new(|x: i32| x + 1);
+        assert!(!callback1.matches(&callback2));
+    }
+}

reactive_graph/src/into_reactive_value.rs

@@ -0,0 +1,67 @@
+#[doc(hidden)]
+pub struct __IntoReactiveValueMarkerBaseCase;
+
+/// A helper trait that works like `Into<T>` but uses a marker generic
+/// to allow more `From` implementations than would be allowed with just `Into<T>`.
+pub trait IntoReactiveValue<T, M> {
+    /// Converts `self` into a `T`.
+    fn into_reactive_value(self) -> T;
+}
+
+// The base case, which allows anything which implements .into() to work:
+impl<T, I> IntoReactiveValue<T, __IntoReactiveValueMarkerBaseCase> for I
+where
+    I: Into<T>,
+{
+    fn into_reactive_value(self) -> T {
+        self.into()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    use crate::{
+        into_reactive_value::IntoReactiveValue,
+        owner::{LocalStorage, Owner},
+        traits::GetUntracked,
+        wrappers::read::Signal,
+    };
+    use typed_builder::TypedBuilder;
+
+    #[test]
+    fn test_into_signal_compiles() {
+        let owner = Owner::new();
+        owner.set();
+
+        #[cfg(not(feature = "nightly"))]
+        let _: Signal<usize> = (|| 2).into_reactive_value();
+        let _: Signal<usize, LocalStorage> = 2.into_reactive_value();
+        #[cfg(not(feature = "nightly"))]
+        let _: Signal<usize, LocalStorage> = (|| 2).into_reactive_value();
+        let _: Signal<String> = "str".into_reactive_value();
+        let _: Signal<String, LocalStorage> = "str".into_reactive_value();
+
+        #[derive(TypedBuilder)]
+        struct Foo {
+            #[builder(setter(
+                fn transform<M>(value: impl IntoReactiveValue<Signal<usize>, M>) {
+                    value.into_reactive_value()
+                }
+            ))]
+            sig: Signal<usize>,
+        }
+
+        assert_eq!(Foo::builder().sig(2).build().sig.get_untracked(), 2);
+        #[cfg(not(feature = "nightly"))]
+        assert_eq!(Foo::builder().sig(|| 2).build().sig.get_untracked(), 2);
+        assert_eq!(
+            Foo::builder()
+                .sig(Signal::stored(2))
+                .build()
+                .sig
+                .get_untracked(),
+            2
+        );
+    }
+}

reactive_graph/src/lib.rs

@@ -90,6 +90,12 @@ pub mod traits;
 pub mod transition;
 pub mod wrappers;
 
+mod into_reactive_value;
+pub use into_reactive_value::*;
+
+/// A standard way to wrap functions and closures to pass them to components.
+pub mod callback;
+
 use computed::ScopedFuture;
 
 #[cfg(all(feature = "nightly", rustc_nightly))]
@@ -97,7 +103,9 @@ mod nightly;
 
 /// Reexports frequently-used traits.
 pub mod prelude {
-    pub use crate::{owner::FromLocal, traits::*};
+    pub use crate::{
+        into_reactive_value::IntoReactiveValue, owner::FromLocal, traits::*,
+    };
 }
 
 // TODO remove this, it's just useful while developing

reactive_graph/src/wrappers.rs

@@ -324,6 +324,22 @@ pub mod read {
         }
     }
 
+    impl<S> From<&'static str> for ArcSignal<String, S>
+    where
+        S: Storage<&'static str> + Storage<String>,
+    {
+        #[track_caller]
+        fn from(value: &'static str) -> Self {
+            Self {
+                inner: SignalTypes::Stored(ArcStoredValue::new(
+                    value.to_string(),
+                )),
+                #[cfg(any(debug_assertions, leptos_debuginfo))]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
     impl<T, S> DefinedAt for ArcSignal<T, S>
     where
         S: Storage<T>,
@@ -1049,6 +1065,13 @@ pub mod read {
         }
     }
 
+    impl From<Signal<&'static str, LocalStorage>> for Signal<String, LocalStorage> {
+        #[track_caller]
+        fn from(value: Signal<&'static str, LocalStorage>) -> Self {
+            Signal::derive_local(move || value.read().to_string())
+        }
+    }
+
     impl From<Signal<&'static str>> for Signal<String, LocalStorage> {
         #[track_caller]
         fn from(value: Signal<&'static str>) -> Self {
@@ -1077,6 +1100,15 @@ pub mod read {
         }
     }
 
+    impl From<Signal<Option<&'static str>, LocalStorage>>
+        for Signal<Option<String>, LocalStorage>
+    {
+        #[track_caller]
+        fn from(value: Signal<Option<&'static str>, LocalStorage>) -> Self {
+            Signal::derive_local(move || value.read().map(str::to_string))
+        }
+    }
+
     impl From<Signal<Option<&'static str>>>
         for Signal<Option<String>, LocalStorage>
     {
@@ -1086,6 +1118,192 @@ pub mod read {
         }
     }
 
+    #[cfg(not(feature = "nightly"))]
+    #[doc(hidden)]
+    pub struct __IntoReactiveValueMarkerSignalFromReactiveClosure;
+    #[cfg(not(feature = "nightly"))]
+    #[doc(hidden)]
+    pub struct __IntoReactiveValueMarkerSignalStrOutputToString;
+    #[cfg(not(feature = "nightly"))]
+    #[doc(hidden)]
+    pub struct __IntoReactiveValueMarkerOptionalSignalFromReactiveClosureAlways;
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            Signal<T, SyncStorage>,
+            __IntoReactiveValueMarkerSignalFromReactiveClosure,
+        > for F
+    where
+        T: Send + Sync + 'static,
+        F: Fn() -> T + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<T, SyncStorage> {
+            Signal::derive(self)
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            ArcSignal<T, SyncStorage>,
+            __IntoReactiveValueMarkerSignalFromReactiveClosure,
+        > for F
+    where
+        T: Send + Sync + 'static,
+        F: Fn() -> T + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<T, SyncStorage> {
+            ArcSignal::derive(self)
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            Signal<T, LocalStorage>,
+            __IntoReactiveValueMarkerSignalFromReactiveClosure,
+        > for F
+    where
+        T: 'static,
+        F: Fn() -> T + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<T, LocalStorage> {
+            Signal::derive_local(self)
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            ArcSignal<T, LocalStorage>,
+            __IntoReactiveValueMarkerSignalFromReactiveClosure,
+        > for F
+    where
+        T: 'static,
+        F: Fn() -> T + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<T, LocalStorage> {
+            ArcSignal::derive_local(self)
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<F>
+        crate::IntoReactiveValue<
+            Signal<String, SyncStorage>,
+            __IntoReactiveValueMarkerSignalStrOutputToString,
+        > for F
+    where
+        F: Fn() -> &'static str + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<String, SyncStorage> {
+            Signal::derive(move || self().to_string())
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<F>
+        crate::IntoReactiveValue<
+            ArcSignal<String, SyncStorage>,
+            __IntoReactiveValueMarkerSignalStrOutputToString,
+        > for F
+    where
+        F: Fn() -> &'static str + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<String, SyncStorage> {
+            ArcSignal::derive(move || self().to_string())
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<F>
+        crate::IntoReactiveValue<
+            Signal<String, LocalStorage>,
+            __IntoReactiveValueMarkerSignalStrOutputToString,
+        > for F
+    where
+        F: Fn() -> &'static str + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<String, LocalStorage> {
+            Signal::derive_local(move || self().to_string())
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<F>
+        crate::IntoReactiveValue<
+            ArcSignal<String, LocalStorage>,
+            __IntoReactiveValueMarkerSignalStrOutputToString,
+        > for F
+    where
+        F: Fn() -> &'static str + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<String, LocalStorage> {
+            ArcSignal::derive_local(move || self().to_string())
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            Signal<Option<T>, SyncStorage>,
+            __IntoReactiveValueMarkerOptionalSignalFromReactiveClosureAlways,
+        > for F
+    where
+        T: Send + Sync + 'static,
+        F: Fn() -> T + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<Option<T>, SyncStorage> {
+            Signal::derive(move || Some(self()))
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            ArcSignal<Option<T>, SyncStorage>,
+            __IntoReactiveValueMarkerOptionalSignalFromReactiveClosureAlways,
+        > for F
+    where
+        T: Send + Sync + 'static,
+        F: Fn() -> T + Send + Sync + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<Option<T>, SyncStorage> {
+            ArcSignal::derive(move || Some(self()))
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            Signal<Option<T>, LocalStorage>,
+            __IntoReactiveValueMarkerOptionalSignalFromReactiveClosureAlways,
+        > for F
+    where
+        T: 'static,
+        F: Fn() -> T + 'static,
+    {
+        fn into_reactive_value(self) -> Signal<Option<T>, LocalStorage> {
+            Signal::derive_local(move || Some(self()))
+        }
+    }
+
+    #[cfg(not(feature = "nightly"))]
+    impl<T, F>
+        crate::IntoReactiveValue<
+            ArcSignal<Option<T>, LocalStorage>,
+            __IntoReactiveValueMarkerOptionalSignalFromReactiveClosureAlways,
+        > for F
+    where
+        T: 'static,
+        F: Fn() -> T + 'static,
+    {
+        fn into_reactive_value(self) -> ArcSignal<Option<T>, LocalStorage> {
+            ArcSignal::derive_local(move || Some(self()))
+        }
+    }
+
     #[allow(deprecated)]
     impl<T> From<MaybeSignal<T>> for Signal<T>
     where