Merge remote-tracking branch 'origin' into 3086

Bumps [denoland/setup-deno](https://github.com/denoland/setup-deno) from 1 to 2.
- [Release notes](https://github.com/denoland/setup-deno/releases)
- [Commits](https://github.com/denoland/setup-deno/compare/v1...v2)

---
updated-dependencies:
- dependency-name: denoland/setup-deno
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/run-cargo-make-task.yml

@@ -94,7 +94,7 @@ jobs:
             fi
           done
       - name: Install Deno
-        uses: denoland/setup-deno@v1
+        uses: denoland/setup-deno@v2
         with:
           deno-version: v1.x
       - name: Maybe install gtk-rs dependencies

examples/router/src/lib.rs

@@ -64,7 +64,7 @@ pub fn RouterExample() -> impl IntoView {
 
 // You can define other routes in their own component.
 // Routes implement the MatchNestedRoutes
-#[component]
+#[component(transparent)]
 pub fn ContactRoutes() -> impl MatchNestedRoutes + Clone {
     view! {
         <ParentRoute path=path!("") view=ContactList>

integrations/actix/src/lib.rs

@@ -1381,39 +1381,41 @@ where
                         ),
                     )
                 } else {
-                    router.route(
-                    path,
-                    match mode {
-                        SsrMode::OutOfOrder => {
-                            render_app_to_stream_with_context(
-                                additional_context_and_method.clone(),
-                                app_fn.clone(),
-                                method,
-                            )
-                        }
-                        SsrMode::PartiallyBlocked => {
-                            render_app_to_stream_with_context_and_replace_blocks(
-                                additional_context_and_method.clone(),
-                                app_fn.clone(),
-                                method,
-                                true,
-                            )
-                        }
-                        SsrMode::InOrder => {
-                            render_app_to_stream_in_order_with_context(
-                                additional_context_and_method.clone(),
-                                app_fn.clone(),
-                                method,
-                            )
-                        }
-                        SsrMode::Async => render_app_async_with_context(
-                            additional_context_and_method.clone(),
-                            app_fn.clone(),
-                            method,
-                        ),
-                        _ => unreachable!()
-                    },
-                )
+                    router
+                        .route(path, web::head().to(HttpResponse::Ok))
+                        .route(
+                            path,
+                            match mode {
+                                SsrMode::OutOfOrder => {
+                                    render_app_to_stream_with_context(
+                                        additional_context_and_method.clone(),
+                                        app_fn.clone(),
+                                        method,
+                                    )
+                                }
+                                SsrMode::PartiallyBlocked => {
+                                    render_app_to_stream_with_context_and_replace_blocks(
+                                        additional_context_and_method.clone(),
+                                        app_fn.clone(),
+                                        method,
+                                        true,
+                                    )
+                                }
+                                SsrMode::InOrder => {
+                                    render_app_to_stream_in_order_with_context(
+                                        additional_context_and_method.clone(),
+                                        app_fn.clone(),
+                                        method,
+                                    )
+                                }
+                                SsrMode::Async => render_app_async_with_context(
+                                    additional_context_and_method.clone(),
+                                    app_fn.clone(),
+                                    method,
+                                ),
+                                _ => unreachable!()
+                            },
+                        )
                 };
             }
         }

leptos/src/await_.rs

@@ -87,7 +87,7 @@ where
     T: Send + Sync + Serialize + DeserializeOwned + 'static,
     Fut: std::future::Future<Output = T> + Send + 'static,
     Chil: FnOnce(&T) -> V + Send + 'static,
-    V: IntoView,
+    V: IntoView + 'static,
 {
     let res = ArcOnceResource::<T>::new_with_options(future, blocking);
     let ready = res.ready();

leptos/src/callback.rs

@@ -41,7 +41,10 @@
 //!
 //! Use `SyncCallback` if the function is not `Sync` and `Send`.
 
-use reactive_graph::owner::{LocalStorage, StoredValue};
+use reactive_graph::{
+    owner::{LocalStorage, StoredValue},
+    traits::WithValue,
+};
 use std::{fmt, rc::Rc, sync::Arc};
 
 /// A wrapper trait for calling callbacks.

leptos/src/provider.rs

@@ -35,7 +35,7 @@ pub fn Provider<T, Chil>(
 ) -> impl IntoView
 where
     T: Send + Sync + 'static,
-    Chil: IntoView,
+    Chil: IntoView + 'static,
 {
     let owner = Owner::current()
         .expect("no current reactive Owner found")

leptos/tests/ssr.rs

@@ -1,5 +1,7 @@
+#[cfg(feature = "ssr")]
 use leptos::html::HtmlElement;
 
+#[cfg(feature = "ssr")]
 #[test]
 fn simple_ssr_test() {
     use leptos::prelude::*;
@@ -20,6 +22,7 @@ fn simple_ssr_test() {
     );
 }
 
+#[cfg(feature = "ssr")]
 #[test]
 fn ssr_test_with_components() {
     use leptos::prelude::*;
@@ -51,6 +54,7 @@ fn ssr_test_with_components() {
     );
 }
 
+#[cfg(feature = "ssr")]
 #[test]
 fn ssr_test_with_snake_case_components() {
     use leptos::prelude::*;
@@ -81,6 +85,7 @@ fn ssr_test_with_snake_case_components() {
     );
 }
 
+#[cfg(feature = "ssr")]
 #[test]
 fn test_classes() {
     use leptos::prelude::*;
@@ -98,6 +103,7 @@ fn test_classes() {
     assert_eq!(rendered.to_html(), "<div class=\"my big  red car\"></div>");
 }
 
+#[cfg(feature = "ssr")]
 #[test]
 fn ssr_with_styles() {
     use leptos::prelude::*;
@@ -119,6 +125,7 @@ fn ssr_with_styles() {
     );
 }
 
+#[cfg(feature = "ssr")]
 #[test]
 fn ssr_option() {
     use leptos::prelude::*;

leptos_dom/src/helpers.rs

@@ -396,8 +396,7 @@ impl IntervalHandle {
     }
 }
 
-/// Repeatedly calls the given function, with a delay of the given duration between calls,
-/// returning a cancelable handle.
+/// Repeatedly calls the given function, with a delay of the given duration between calls.
 /// See [`setInterval()`](https://developer.mozilla.org/en-US/docs/Web/API/setInterval).
 #[cfg_attr(
   feature = "tracing",

leptos_macro/Cargo.toml

@@ -51,7 +51,15 @@ axum = ["server_fn_macro/axum"]
 
 [package.metadata.cargo-all-features]
 denylist = ["nightly", "tracing", "trace-component-props"]
-skip_feature_sets = [["csr", "hydrate"], ["hydrate", "csr"], ["hydrate", "ssr"]]
+skip_feature_sets = [
+	["csr", "hydrate"],
+	["hydrate", "csr"],
+	["hydrate", "ssr"],
+	["actix", "axum"]
+]
 
 [package.metadata.docs.rs]
 rustdoc-args = ["--generate-link-to-definition"]
+
+[lints.rust]
+unexpected_cfgs = { level = "warn", check-cfg = ['cfg(erase_components)'] }

leptos_macro/src/component.rs

@@ -18,6 +18,7 @@ use syn::{
 };
 
 pub struct Model {
+    is_transparent: bool,
     island: Option<String>,
     docs: Docs,
     unknown_attrs: UnknownAttrs,
@@ -62,6 +63,7 @@ impl Parse for Model {
         });
 
         Ok(Self {
+            is_transparent: false,
             island: None,
             docs,
             unknown_attrs,
@@ -102,6 +104,7 @@ pub fn convert_from_snake_case(name: &Ident) -> Ident {
 impl ToTokens for Model {
     fn to_tokens(&self, tokens: &mut TokenStream) {
         let Self {
+            is_transparent,
             island,
             docs,
             unknown_attrs,
@@ -116,20 +119,22 @@ impl ToTokens for Model {
         let no_props = props.is_empty();
 
         // check for components that end ;
-        let ends_semi =
-            body.block.stmts.iter().last().and_then(|stmt| match stmt {
-                Stmt::Item(Item::Macro(mac)) => mac.semi_token.as_ref(),
-                _ => None,
-            });
-        if let Some(semi) = ends_semi {
-            proc_macro_error2::emit_error!(
-                semi.span(),
-                "A component that ends with a `view!` macro followed by a \
-                 semicolon will return (), an empty view. This is usually an \
-                 accident, not intentional, so we prevent it. If you’d like \
-                 to return (), you can do it it explicitly by returning () as \
-                 the last item from the component."
-            );
+        if !is_transparent {
+            let ends_semi =
+                body.block.stmts.iter().last().and_then(|stmt| match stmt {
+                    Stmt::Item(Item::Macro(mac)) => mac.semi_token.as_ref(),
+                    _ => None,
+                });
+            if let Some(semi) = ends_semi {
+                proc_macro_error2::emit_error!(
+                    semi.span(),
+                    "A component that ends with a `view!` macro followed by a \
+                     semicolon will return (), an empty view. This is usually \
+                     an accident, not intentional, so we prevent it. If you’d \
+                     like to return (), you can do it it explicitly by \
+                     returning () as the last item from the component."
+                );
+            }
         }
 
         //body.sig.ident = format_ident!("__{}", body.sig.ident);
@@ -265,14 +270,30 @@ impl ToTokens for Model {
             }
         };
 
-        let component = quote! {
-            ::leptos::prelude::untrack(
-                move || {
-                    #tracing_guard_expr
-                    #tracing_props_expr
-                    #body_expr
-                }
-            )
+        let component = if *is_transparent {
+            body_expr
+        } else if cfg!(erase_components) {
+            quote! {
+                ::leptos::prelude::IntoAny::into_any(
+                    ::leptos::prelude::untrack(
+                        move || {
+                            #tracing_guard_expr
+                            #tracing_props_expr
+                            #body_expr
+                        }
+                    )
+                )
+            }
+        } else {
+            quote! {
+                ::leptos::prelude::untrack(
+                    move || {
+                        #tracing_guard_expr
+                        #tracing_props_expr
+                        #body_expr
+                    }
+                )
+            }
         };
 
         // add island wrapper if island
@@ -520,6 +541,13 @@ impl ToTokens for Model {
 }
 
 impl Model {
+    #[allow(clippy::wrong_self_convention)]
+    pub fn is_transparent(mut self, is_transparent: bool) -> Self {
+        self.is_transparent = is_transparent;
+
+        self
+    }
+
     #[allow(clippy::wrong_self_convention)]
     pub fn with_island(mut self, island: Option<String>) -> Self {
         self.island = island;

leptos_macro/src/lib.rs

@@ -535,11 +535,24 @@ pub fn include_view(tokens: TokenStream) -> TokenStream {
 /// ```
 #[proc_macro_error2::proc_macro_error]
 #[proc_macro_attribute]
-pub fn component(
-    _args: proc_macro::TokenStream,
-    s: TokenStream,
-) -> TokenStream {
-    component_macro(s, None)
+pub fn component(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
+    let is_transparent = if !args.is_empty() {
+        let transparent = parse_macro_input!(args as syn::Ident);
+
+        if transparent != "transparent" {
+            abort!(
+                transparent,
+                "only `transparent` is supported";
+                help = "try `#[component(transparent)]` or `#[component]`"
+            );
+        }
+
+        true
+    } else {
+        false
+    };
+
+    component_macro(s, is_transparent, None)
 }
 
 /// Defines a component as an interactive island when you are using the
@@ -615,17 +628,37 @@ pub fn component(
 /// ```
 #[proc_macro_error2::proc_macro_error]
 #[proc_macro_attribute]
-pub fn island(_args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
+pub fn island(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
+    let is_transparent = if !args.is_empty() {
+        let transparent = parse_macro_input!(args as syn::Ident);
+
+        if transparent != "transparent" {
+            abort!(
+                transparent,
+                "only `transparent` is supported";
+                help = "try `#[component(transparent)]` or `#[component]`"
+            );
+        }
+
+        true
+    } else {
+        false
+    };
+
     let island_src = s.to_string();
-    component_macro(s, Some(island_src))
+    component_macro(s, is_transparent, Some(island_src))
 }
 
-fn component_macro(s: TokenStream, island: Option<String>) -> TokenStream {
+fn component_macro(
+    s: TokenStream,
+    is_transparent: bool,
+    island: Option<String>,
+) -> TokenStream {
     let mut dummy = syn::parse::<DummyModel>(s.clone());
     let parse_result = syn::parse::<component::Model>(s);
 
     if let (Ok(ref mut unexpanded), Ok(model)) = (&mut dummy, parse_result) {
-        let expanded = model.with_island(island).into_token_stream();
+        let expanded = model.is_transparent(is_transparent).with_island(island).into_token_stream();
         if !matches!(unexpanded.vis, Visibility::Public(_)) {
             unexpanded.vis = Visibility::Public(Pub {
                 span: unexpanded.vis.span(),

leptos_macro/src/view/mod.rs

@@ -179,7 +179,7 @@ fn is_inert_element(orig_node: &Node<impl CustomNode>) -> bool {
 }
 
 enum Item<'a, T> {
-    Node(&'a Node<T>),
+    Node(&'a Node<T>, bool),
     ClosingTag(String),
 }
 
@@ -290,10 +290,11 @@ impl<'a> InertElementBuilder<'a> {
 
 fn inert_element_to_tokens(
     node: &Node<impl CustomNode>,
+    escape_text: bool,
     global_class: Option<&TokenTree>,
 ) -> Option<TokenStream> {
     let mut html = InertElementBuilder::new(global_class);
-    let mut nodes = VecDeque::from([Item::Node(node)]);
+    let mut nodes = VecDeque::from([Item::Node(node, escape_text)]);
 
     while let Some(current) = nodes.pop_front() {
         match current {
@@ -303,21 +304,32 @@ fn inert_element_to_tokens(
                 html.push_str(&tag);
                 html.push('>');
             }
-            Item::Node(current) => {
+            Item::Node(current, escape) => {
                 match current {
                     Node::RawText(raw) => {
                         let text = raw.to_string_best();
-                        let text = html_escape::encode_text(&text);
+                        let text = if escape {
+                            html_escape::encode_text(&text)
+                        } else {
+                            text.into()
+                        };
                         html.push_str(&text);
                     }
                     Node::Text(text) => {
                         let text = text.value_string();
-                        let text = html_escape::encode_text(&text);
+                        let text = if escape {
+                            html_escape::encode_text(&text)
+                        } else {
+                            text.into()
+                        };
                         html.push_str(&text);
                     }
                     Node::Element(node) => {
                         let self_closing = is_self_closing(node);
                         let el_name = node.name().to_string();
+                        let escape = el_name != "script"
+                            && el_name != "style"
+                            && el_name != "textarea";
 
                         // opening tag
                         html.push('<');
@@ -364,7 +376,7 @@ fn inert_element_to_tokens(
                             nodes.push_front(Item::ClosingTag(el_name));
                             let children = node.children.iter().rev();
                             for child in children {
-                                nodes.push_front(Item::Node(child));
+                                nodes.push_front(Item::Node(child, escape));
                             }
                         }
                     }
@@ -548,7 +560,9 @@ fn node_to_tokens(
             view_marker,
             disable_inert_html,
         ),
-        Node::Block(block) => Some(quote! { #block }),
+        Node::Block(block) => {
+            Some(quote! { ::leptos::prelude::IntoRender::into_render(#block) })
+        }
         Node::Text(text) => Some(text_to_tokens(&text.value)),
         Node::RawText(raw) => {
             let text = raw.to_string_best();
@@ -557,7 +571,11 @@ fn node_to_tokens(
         }
         Node::Element(el_node) => {
             if !top_level && is_inert {
-                inert_element_to_tokens(node, global_class)
+                let el_name = el_node.name().to_string();
+                let escape = el_name != "script"
+                    && el_name != "style"
+                    && el_name != "textarea";
+                inert_element_to_tokens(node, escape, global_class)
             } else {
                 element_to_tokens(
                     el_node,
@@ -725,6 +743,11 @@ pub(crate) fn element_to_tokens(
             quote! { ::leptos::tachys::html::element::#custom(#name) }
         } else if is_svg_element(&tag) {
             parent_type = TagType::Svg;
+            let name = if tag == "use" || tag == "use_" {
+                Ident::new_raw("use", name.span()).to_token_stream()
+            } else {
+                name.to_token_stream()
+            };
             quote! { ::leptos::tachys::svg::#name() }
         } else if is_math_ml_element(&tag) {
             parent_type = TagType::Math;
@@ -878,7 +901,7 @@ fn attribute_to_tokens(
                     NodeName::Path(path) => path.path.get_ident(),
                     _ => unreachable!(),
                 };
-                let value = attribute_value(node);
+                let value = attribute_value(node, false);
                 quote! {
                     .#node_ref(#value)
                 }
@@ -928,13 +951,13 @@ fn attribute_to_tokens(
                 // we don't provide statically-checked methods for SVG attributes
                 || (tag_type == TagType::Svg && name != "inner_html")
             {
-                let value = attribute_value(node);
+                let value = attribute_value(node, true);
                 quote! {
                     .attr(#name, #value)
                 }
             } else {
                 let key = attribute_name(&node.key);
-                let value = attribute_value(node);
+                let value = attribute_value(node, true);
 
                 // special case of global_class and class attribute
                 if &node.key.to_string() == "class"
@@ -971,11 +994,11 @@ pub(crate) fn attribute_absolute(
                 let id = &parts[0];
                 match id {
                     NodeNameFragment::Ident(id) => {
-                        let value = attribute_value(node);
                         // ignore `let:` and `clone:`
                         if id == "let" || id == "clone" {
                             None
                         } else if id == "attr" {
+                        let value = attribute_value(node, true);
                             let key = &parts[1];
                             let key_name = key.to_string();
                             if key_name == "class" || key_name == "style" {
@@ -983,6 +1006,7 @@ pub(crate) fn attribute_absolute(
                                     quote! { ::leptos::tachys::html::#key::#key(#value) },
                                 )
                             } else if key_name == "aria" {
+                                let value = attribute_value(node, true);
                                 let mut parts_iter = parts.iter();
                                 parts_iter.next();
                                 let fn_name = parts_iter.map(|p| p.to_string()).collect::<Vec<String>>().join("_");
@@ -1011,6 +1035,7 @@ pub(crate) fn attribute_absolute(
                                 },
                             )
                         } else if id == "style" || id == "class" {
+                            let value = attribute_value(node, false);
                             let key = &node.key.to_string();
                             let key = key
                                 .replacen("style:", "", 1)
@@ -1019,6 +1044,7 @@ pub(crate) fn attribute_absolute(
                                 quote! { ::leptos::tachys::html::#id::#id((#key, #value)) },
                             )
                         } else if id == "prop" {
+                            let value = attribute_value(node, false);
                             let key = &node.key.to_string();
                             let key = key.replacen("prop:", "", 1);
                             Some(
@@ -1075,7 +1101,7 @@ pub(crate) fn two_way_binding_to_tokens(
     name: &str,
     node: &KeyedAttribute,
 ) -> TokenStream {
-    let value = attribute_value(node);
+    let value = attribute_value(node, false);
 
     let ident =
         format_ident!("{}", name.to_case(UpperCamel), span = node.key.span());
@@ -1100,7 +1126,7 @@ pub(crate) fn event_type_and_handler(
     name: &str,
     node: &KeyedAttribute,
 ) -> (TokenStream, TokenStream, TokenStream) {
-    let handler = attribute_value(node);
+    let handler = attribute_value(node, false);
 
     let (event_type, is_custom, is_force_undelegated, is_targeted) =
         parse_event_name(name);
@@ -1157,7 +1183,7 @@ fn class_to_tokens(
     class: TokenStream,
     class_name: Option<&str>,
 ) -> TokenStream {
-    let value = attribute_value(node);
+    let value = attribute_value(node, false);
     if let Some(class_name) = class_name {
         quote! {
             .#class((#class_name, #value))
@@ -1174,7 +1200,7 @@ fn style_to_tokens(
     style: TokenStream,
     style_name: Option<&str>,
 ) -> TokenStream {
-    let value = attribute_value(node);
+    let value = attribute_value(node, false);
     if let Some(style_name) = style_name {
         quote! {
             .#style((#style_name, #value))
@@ -1191,7 +1217,7 @@ fn prop_to_tokens(
     prop: TokenStream,
     key: &str,
 ) -> TokenStream {
-    let value = attribute_value(node);
+    let value = attribute_value(node, false);
     quote! {
         .#prop(#key, #value)
     }
@@ -1348,7 +1374,10 @@ fn attribute_name(name: &NodeName) -> TokenStream {
     }
 }
 
-fn attribute_value(attr: &KeyedAttribute) -> TokenStream {
+fn attribute_value(
+    attr: &KeyedAttribute,
+    is_attribute_proper: bool,
+) -> TokenStream {
     match attr.possible_value.to_value() {
         None => quote! { true },
         Some(value) => match &value.value {
@@ -1363,14 +1392,26 @@ fn attribute_value(attr: &KeyedAttribute) -> TokenStream {
                     }
                 }
 
-                quote! {
-                    {#expr}
+                if matches!(expr, Expr::Lit(_)) || !is_attribute_proper {
+                    quote! {
+                        #expr
+                    }
+                } else {
+                    quote! {
+                        ::leptos::prelude::IntoAttributeValue::into_attribute_value(#expr)
+                    }
                 }
             }
             // any value in braces: expand as-is to give proper r-a support
             KVAttributeValue::InvalidBraced(block) => {
-                quote! {
-                    #block
+                if is_attribute_proper {
+                    quote! {
+                        ::leptos::prelude::IntoAttributeValue::into_attribute_value(#block)
+                    }
+                } else {
+                    quote! {
+                        #block
+                    }
                 }
             }
         },

leptos_macro/tests/ui.rs

@@ -1,3 +1,4 @@
+#[cfg(not(erase_components))]
 #[test]
 fn ui() {
     let t = trybuild::TestCases::new();

leptos_server/src/local_resource.rs

@@ -35,10 +35,10 @@ impl<T> Clone for ArcLocalResource<T> {
 
 impl<T> ArcLocalResource<T> {
     #[track_caller]
-    pub fn new<Fut>(fetcher: impl Fn() -> Fut + Send + Sync + 'static) -> Self
+    pub fn new<Fut>(fetcher: impl Fn() -> Fut + 'static) -> Self
     where
-        T: Send + Sync + 'static,
-        Fut: Future<Output = T> + Send + 'static,
+        T: 'static,
+        Fut: Future<Output = T> + 'static,
     {
         let fetcher = move || {
             let fut = fetcher();
@@ -60,7 +60,7 @@ impl<T> ArcLocalResource<T> {
             }
         };
         Self {
-            data: ArcAsyncDerived::new(fetcher),
+            data: ArcAsyncDerived::new_unsync(fetcher),
             #[cfg(debug_assertions)]
             defined_at: Location::caller(),
         }
@@ -103,7 +103,7 @@ impl<T> DefinedAt for ArcLocalResource<T> {
 
 impl<T> ReadUntracked for ArcLocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     type Value = ReadGuard<Option<T>, AsyncPlain<Option<T>>>;
 
@@ -201,7 +201,7 @@ impl<T> LocalResource<T> {
     pub fn new<Fut>(fetcher: impl Fn() -> Fut + 'static) -> Self
     where
         T: 'static,
-        Fut: Future<Output = T> + Send + 'static,
+        Fut: Future<Output = T> + 'static,
     {
         let fetcher = move || {
             let fut = fetcher();
@@ -230,7 +230,7 @@ impl<T> LocalResource<T> {
                 let fetcher = SendWrapper::new(fetcher);
                 AsyncDerived::new(move || {
                     let fut = fetcher();
-                    async move { SendWrapper::new(fut.await) }
+                    SendWrapper::new(async move { SendWrapper::new(fut.await) })
                 })
             },
             #[cfg(debug_assertions)]
@@ -280,7 +280,7 @@ impl<T> DefinedAt for LocalResource<T> {
 
 impl<T> ReadUntracked for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     type Value =
         ReadGuard<Option<SendWrapper<T>>, AsyncPlain<Option<SendWrapper<T>>>>;
@@ -307,7 +307,7 @@ impl<T: 'static> IsDisposed for LocalResource<T> {
 
 impl<T: 'static> ToAnySource for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     fn to_any_source(&self) -> AnySource {
         self.data.to_any_source()
@@ -316,7 +316,7 @@ where
 
 impl<T: 'static> ToAnySubscriber for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     fn to_any_subscriber(&self) -> AnySubscriber {
         self.data.to_any_subscriber()
@@ -325,7 +325,7 @@ where
 
 impl<T> Source for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     fn add_subscriber(&self, subscriber: AnySubscriber) {
         self.data.add_subscriber(subscriber)
@@ -342,7 +342,7 @@ where
 
 impl<T> ReactiveNode for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     fn mark_dirty(&self) {
         self.data.mark_dirty();
@@ -363,7 +363,7 @@ where
 
 impl<T> Subscriber for LocalResource<T>
 where
-    T: Send + Sync + 'static,
+    T: 'static,
 {
     fn add_source(&self, source: AnySource) {
         self.data.add_source(source);

reactive_graph/src/actions/action.rs

@@ -1,9 +1,12 @@
 use crate::{
     computed::{ArcMemo, Memo},
     diagnostics::is_suppressing_resource_load,
-    owner::{ArenaItem, FromLocal, LocalStorage, Storage, SyncStorage},
+    owner::{
+        ArcStoredValue, ArenaItem, FromLocal, LocalStorage, Storage,
+        SyncStorage,
+    },
     signal::{ArcRwSignal, RwSignal},
-    traits::{DefinedAt, Dispose, Get, GetUntracked, Update},
+    traits::{DefinedAt, Dispose, Get, GetUntracked, GetValue, Update},
     unwrap_signal,
 };
 use any_spawner::Executor;
@@ -93,6 +96,7 @@ pub struct ArcAction<I, O> {
     input: ArcRwSignal<Option<I>>,
     value: ArcRwSignal<Option<O>>,
     version: ArcRwSignal<usize>,
+    dispatched: ArcStoredValue<usize>,
     #[allow(clippy::complexity)]
     action_fn: Arc<
         dyn Fn(&I) -> Pin<Box<dyn Future<Output = O> + Send>> + Send + Sync,
@@ -108,6 +112,7 @@ impl<I, O> Clone for ArcAction<I, O> {
             input: self.input.clone(),
             value: self.value.clone(),
             version: self.version.clone(),
+            dispatched: self.dispatched.clone(),
             action_fn: self.action_fn.clone(),
             #[cfg(debug_assertions)]
             defined_at: self.defined_at,
@@ -191,6 +196,7 @@ where
             input: Default::default(),
             value: ArcRwSignal::new(value),
             version: Default::default(),
+            dispatched: Default::default(),
             action_fn: Arc::new(move |input| Box::pin(action_fn(input))),
             #[cfg(debug_assertions)]
             defined_at: Location::caller(),
@@ -230,14 +236,14 @@ where
 
             // Update the state before loading
             self.in_flight.update(|n| *n += 1);
-            let current_version =
-                self.version.try_get_untracked().unwrap_or_default();
+            let current_version = self.dispatched.get_value();
             self.input.try_update(|inp| *inp = Some(input));
 
             // Spawn the task
             crate::spawn({
                 let input = self.input.clone();
                 let version = self.version.clone();
+                let dispatched = self.dispatched.clone();
                 let value = self.value.clone();
                 let in_flight = self.in_flight.clone();
                 async move {
@@ -249,7 +255,7 @@ where
                         // otherwise, update the value
                         result = fut => {
                             in_flight.update(|n| *n = n.saturating_sub(1));
-                            let is_latest = version.get_untracked() <= current_version;
+                            let is_latest = dispatched.get_value() <= current_version;
                             if is_latest {
                                 version.update(|n| *n += 1);
                                 value.update(|n| *n = Some(result));
@@ -282,8 +288,7 @@ where
 
             // Update the state before loading
             self.in_flight.update(|n| *n += 1);
-            let current_version =
-                self.version.try_get_untracked().unwrap_or_default();
+            let current_version = self.dispatched.get_value();
             self.input.try_update(|inp| *inp = Some(input));
 
             // Spawn the task
@@ -291,6 +296,7 @@ where
                 let input = self.input.clone();
                 let version = self.version.clone();
                 let value = self.value.clone();
+                let dispatched = self.dispatched.clone();
                 let in_flight = self.in_flight.clone();
                 async move {
                     select! {
@@ -301,7 +307,7 @@ where
                         // otherwise, update the value
                         result = fut => {
                             in_flight.update(|n| *n = n.saturating_sub(1));
-                            let is_latest = version.get_untracked() <= current_version;
+                            let is_latest = dispatched.get_value() <= current_version;
                             if is_latest {
                                 version.update(|n| *n += 1);
                                 value.update(|n| *n = Some(result));
@@ -351,6 +357,7 @@ where
             input: Default::default(),
             value: ArcRwSignal::new(value),
             version: Default::default(),
+            dispatched: Default::default(),
             action_fn: Arc::new(move |input| {
                 Box::pin(SendWrapper::new(action_fn(input)))
             }),

reactive_graph/src/computed.rs

@@ -15,6 +15,7 @@ use crate::{
 };
 pub use arc_memo::*;
 pub use async_derived::*;
+pub(crate) use inner::MemoInner;
 pub use memo::*;
 pub use selector::*;
 

reactive_graph/src/owner.rs

@@ -12,12 +12,14 @@ use std::{
     sync::{Arc, RwLock, Weak},
 };
 
+mod arc_stored_value;
 mod arena;
 mod arena_item;
 mod context;
 mod storage;
 mod stored_value;
 use self::arena::Arena;
+pub use arc_stored_value::ArcStoredValue;
 #[cfg(feature = "sandboxed-arenas")]
 pub use arena::sandboxed::Sandboxed;
 #[cfg(feature = "sandboxed-arenas")]

reactive_graph/src/owner/arc_stored_value.rs

@@ -0,0 +1,126 @@
+use crate::{
+    signal::guards::{Plain, ReadGuard, UntrackedWriteGuard},
+    traits::{DefinedAt, IsDisposed, ReadValue, WriteValue},
+};
+use std::{
+    fmt::{Debug, Formatter},
+    hash::Hash,
+    panic::Location,
+    sync::{Arc, RwLock},
+};
+
+/// A reference-counted getter for any value non-reactively.
+///
+/// This is a reference-counted value, which is `Clone` but not `Copy`.
+/// For arena-allocated `Copy` values, use [`StoredValue`](super::StoredValue).
+///
+/// This allows you to create a stable reference for any value by storing it within
+/// the reactive system. Unlike e.g. [`ArcRwSignal`](crate::signal::ArcRwSignal), it is not reactive;
+/// accessing it does not cause effects to subscribe, and
+/// updating it does not notify anything else.
+pub struct ArcStoredValue<T> {
+    #[cfg(debug_assertions)]
+    defined_at: &'static Location<'static>,
+    value: Arc<RwLock<T>>,
+}
+
+impl<T> Clone for ArcStoredValue<T> {
+    fn clone(&self) -> Self {
+        Self {
+            #[cfg(debug_assertions)]
+            defined_at: self.defined_at,
+            value: Arc::clone(&self.value),
+        }
+    }
+}
+
+impl<T> Debug for ArcStoredValue<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
+        f.debug_struct("ArcStoredValue")
+            .field("type", &std::any::type_name::<T>())
+            .field("value", &Arc::as_ptr(&self.value))
+            .finish()
+    }
+}
+
+impl<T: Default> Default for ArcStoredValue<T> {
+    #[track_caller]
+    fn default() -> Self {
+        Self {
+            #[cfg(debug_assertions)]
+            defined_at: Location::caller(),
+            value: Arc::new(RwLock::new(T::default())),
+        }
+    }
+}
+
+impl<T> PartialEq for ArcStoredValue<T> {
+    fn eq(&self, other: &Self) -> bool {
+        Arc::ptr_eq(&self.value, &other.value)
+    }
+}
+
+impl<T> Eq for ArcStoredValue<T> {}
+
+impl<T> Hash for ArcStoredValue<T> {
+    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
+        std::ptr::hash(&Arc::as_ptr(&self.value), state);
+    }
+}
+
+impl<T> DefinedAt for ArcStoredValue<T> {
+    fn defined_at(&self) -> Option<&'static Location<'static>> {
+        #[cfg(debug_assertions)]
+        {
+            Some(self.defined_at)
+        }
+        #[cfg(not(debug_assertions))]
+        {
+            None
+        }
+    }
+}
+
+impl<T> ArcStoredValue<T> {
+    /// Creates a new stored value, taking the initial value as its argument.
+    #[cfg_attr(
+        feature = "tracing",
+        tracing::instrument(level = "trace", skip_all)
+    )]
+    #[track_caller]
+    pub fn new(value: T) -> Self {
+        Self {
+            #[cfg(debug_assertions)]
+            defined_at: Location::caller(),
+            value: Arc::new(RwLock::new(value)),
+        }
+    }
+}
+
+impl<T> ReadValue for ArcStoredValue<T>
+where
+    T: 'static,
+{
+    type Value = ReadGuard<T, Plain<T>>;
+
+    fn try_read_value(&self) -> Option<ReadGuard<T, Plain<T>>> {
+        Plain::try_new(Arc::clone(&self.value)).map(ReadGuard::new)
+    }
+}
+
+impl<T> WriteValue for ArcStoredValue<T>
+where
+    T: 'static,
+{
+    type Value = T;
+
+    fn try_write_value(&self) -> Option<UntrackedWriteGuard<T>> {
+        UntrackedWriteGuard::try_new(self.value.clone())
+    }
+}
+
+impl<T> IsDisposed for ArcStoredValue<T> {
+    fn is_disposed(&self) -> bool {
+        false
+    }
+}

reactive_graph/src/owner/stored_value.rs

@@ -1,14 +1,16 @@
-use super::{ArenaItem, LocalStorage, Storage, SyncStorage};
+use super::{
+    arc_stored_value::ArcStoredValue, ArenaItem, LocalStorage, Storage,
+    SyncStorage,
+};
 use crate::{
     signal::guards::{Plain, ReadGuard, UntrackedWriteGuard},
-    traits::{DefinedAt, Dispose, IsDisposed},
+    traits::{DefinedAt, Dispose, IsDisposed, ReadValue, WriteValue},
     unwrap_signal,
 };
-use or_poisoned::OrPoisoned;
 use std::{
+    fmt::{Debug, Formatter},
     hash::Hash,
     panic::Location,
-    sync::{Arc, RwLock},
 };
 
 /// A **non-reactive**, `Copy` handle for any value.
@@ -18,9 +20,8 @@ use std::{
 /// and [`RwSignal`](crate::signal::RwSignal)), it is `Copy` and `'static`. Unlike the signal
 /// types, it is not reactive; accessing it does not cause effects to subscribe, and
 /// updating it does not notify anything else.
-#[derive(Debug)]
 pub struct StoredValue<T, S = SyncStorage> {
-    value: ArenaItem<Arc<RwLock<T>>, S>,
+    value: ArenaItem<ArcStoredValue<T>, S>,
     #[cfg(debug_assertions)]
     defined_at: &'static Location<'static>,
 }
@@ -33,6 +34,18 @@ impl<T, S> Clone for StoredValue<T, S> {
     }
 }
 
+impl<T, S> Debug for StoredValue<T, S>
+where
+    S: Debug,
+{
+    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
+        f.debug_struct("StoredValue")
+            .field("type", &std::any::type_name::<T>())
+            .field("value", &self.value)
+            .finish()
+    }
+}
+
 impl<T, S> PartialEq for StoredValue<T, S> {
     fn eq(&self, other: &Self) -> bool {
         self.value == other.value
@@ -63,13 +76,13 @@ impl<T, S> DefinedAt for StoredValue<T, S> {
 impl<T, S> StoredValue<T, S>
 where
     T: 'static,
-    S: Storage<Arc<RwLock<T>>>,
+    S: Storage<ArcStoredValue<T>>,
 {
     /// Stores the given value in the arena allocator.
     #[track_caller]
     pub fn new_with_storage(value: T) -> Self {
         Self {
-            value: ArenaItem::new_with_storage(Arc::new(RwLock::new(value))),
+            value: ArenaItem::new_with_storage(ArcStoredValue::new(value)),
             #[cfg(debug_assertions)]
             defined_at: Location::caller(),
         }
@@ -79,7 +92,7 @@ where
 impl<T, S> Default for StoredValue<T, S>
 where
     T: Default + 'static,
-    S: Storage<Arc<RwLock<T>>>,
+    S: Storage<ArcStoredValue<T>>,
 {
     #[track_caller] // Default trait is not annotated with #[track_caller]
     fn default() -> Self {
@@ -109,268 +122,31 @@ where
     }
 }
 
-impl<T, S: Storage<Arc<RwLock<T>>>> StoredValue<T, S> {
-    /// Returns an [`Option`] of applying a function to the value within the [`StoredValue`].
-    ///
-    /// If the owner of the reactive node has not been disposed [`Some`] is returned. Calling this
-    /// function after the owner has been disposed will always return [`None`].
-    ///
-    /// See [`StoredValue::with_value`] for a version that panics in the case of the owner being
-    /// disposed.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    /// # use reactive_graph::traits::Dispose;
-    ///
-    /// // Does not implement Clone
-    /// struct Data {
-    ///     rows: Vec<u8>,
-    /// }
-    ///
-    /// let data = StoredValue::new(Data {
-    ///     rows: vec![0, 1, 2, 3, 4],
-    /// });
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static.
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let length_fn = move || data.try_with_value(|inner| inner.rows.len());
-    ///
-    /// let sum = data.try_with_value(|inner| inner.rows.iter().sum::<u8>());
-    ///
-    /// assert_eq!(sum, Some(10));
-    /// assert_eq!(length_fn(), Some(5));
-    ///
-    /// // You should not call dispose yourself in normal user code.
-    /// // This is shown here for the sake of the example.
-    /// data.dispose();
-    ///
-    /// let last = data.try_with_value(|inner| inner.rows.last().cloned());
-    ///
-    /// assert_eq!(last, None);
-    /// assert_eq!(length_fn(), None);
-    /// ```
-    #[track_caller]
-    pub fn try_with_value<U>(&self, fun: impl FnOnce(&T) -> U) -> Option<U> {
+impl<T, S> ReadValue for StoredValue<T, S>
+where
+    T: 'static,
+    S: Storage<ArcStoredValue<T>>,
+{
+    type Value = ReadGuard<T, Plain<T>>;
+
+    fn try_read_value(&self) -> Option<ReadGuard<T, Plain<T>>> {
         self.value
             .try_get_value()
-            .map(|inner| fun(&*inner.read().or_poisoned()))
+            .and_then(|inner| inner.try_read_value())
     }
+}
 
-    /// Returns the output of applying a function to the value within the [`StoredValue`].
-    ///
-    /// # Panics
-    ///
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_with_value`] for a version without panic.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    ///
-    /// // Does not implement Clone
-    /// struct Data {
-    ///     rows: Vec<u8>,
-    /// }
-    ///
-    /// let data = StoredValue::new(Data {
-    ///     rows: vec![1, 2, 3],
-    /// });
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static.
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let length_fn = move || data.with_value(|inner| inner.rows.len());
-    ///
-    /// let sum = data.with_value(|inner| inner.rows.iter().sum::<u8>());
-    ///
-    /// assert_eq!(sum, 6);
-    /// assert_eq!(length_fn(), 3);
-    /// ```
-    #[track_caller]
-    pub fn with_value<U>(&self, fun: impl FnOnce(&T) -> U) -> U {
-        self.try_with_value(fun)
-            .unwrap_or_else(unwrap_signal!(self))
-    }
+impl<T, S> WriteValue for StoredValue<T, S>
+where
+    T: 'static,
+    S: Storage<ArcStoredValue<T>>,
+{
+    type Value = T;
 
-    /// Returns a read guard to the stored data, or `None` if the owner of the reactive node has been disposed.
-    #[track_caller]
-    pub fn try_read_value(&self) -> Option<ReadGuard<T, Plain<T>>> {
+    fn try_write_value(&self) -> Option<UntrackedWriteGuard<T>> {
         self.value
             .try_get_value()
-            .and_then(|inner| Plain::try_new(inner).map(ReadGuard::new))
-    }
-
-    /// Returns a read guard to the stored data.
-    ///
-    /// # Panics
-    ///
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_read_value`] for a version without panic.
-    #[track_caller]
-    pub fn read_value(&self) -> ReadGuard<T, Plain<T>> {
-        self.try_read_value().unwrap_or_else(unwrap_signal!(self))
-    }
-
-    /// Returns a write guard to the stored data, or `None` if the owner of the reactive node has been disposed.
-    #[track_caller]
-    pub fn try_write_value(&self) -> Option<UntrackedWriteGuard<T>> {
-        self.value
-            .try_get_value()
-            .and_then(|inner| UntrackedWriteGuard::try_new(inner))
-    }
-
-    /// Returns a write guard to the stored data.
-    ///
-    /// # Panics
-    ///
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_write_value`] for a version without panic.
-    #[track_caller]
-    pub fn write_value(&self) -> UntrackedWriteGuard<T> {
-        self.try_write_value().unwrap_or_else(unwrap_signal!(self))
-    }
-
-    /// Updates the current value by applying the given closure, returning the return value of the
-    /// closure, or `None` if the value has already been disposed.
-    pub fn try_update_value<U>(
-        &self,
-        fun: impl FnOnce(&mut T) -> U,
-    ) -> Option<U> {
-        self.value
-            .try_get_value()
-            .map(|inner| fun(&mut *inner.write().or_poisoned()))
-    }
-
-    /// Updates the value within [`StoredValue`] by applying a function to it.
-    ///
-    /// # Panics
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_update_value`] for a version without panic.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    ///
-    /// #[derive(Default)] // Does not implement Clone
-    /// struct Data {
-    ///     rows: Vec<u8>,
-    /// }
-    ///
-    /// let data = StoredValue::new(Data::default());
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static.
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let push_next = move || {
-    ///     data.update_value(|inner| match inner.rows.last().as_deref() {
-    ///         Some(n) => inner.rows.push(n + 1),
-    ///         None => inner.rows.push(0),
-    ///     })
-    /// };
-    ///
-    /// data.update_value(|inner| inner.rows = vec![5, 6, 7]);
-    /// data.with_value(|inner| assert_eq!(inner.rows.last(), Some(&7)));
-    ///
-    /// push_next();
-    /// data.with_value(|inner| assert_eq!(inner.rows.last(), Some(&8)));
-    ///
-    /// data.update_value(|inner| {
-    ///     std::mem::take(inner) // sets Data back to default
-    /// });
-    /// data.with_value(|inner| assert!(inner.rows.is_empty()));
-    /// ```
-    pub fn update_value<U>(&self, fun: impl FnOnce(&mut T) -> U) {
-        self.try_update_value(fun);
-    }
-
-    /// Sets the value within [`StoredValue`].
-    ///
-    /// Returns [`Some`] containing the passed value if the owner of the reactive node has been
-    /// disposed.
-    ///
-    /// For types that do not implement [`Clone`], or in cases where allocating the entire object
-    /// would be too expensive, prefer [`StoredValue::try_update_value`].
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    /// # use reactive_graph::traits::Dispose;
-    ///
-    /// let data = StoredValue::new(String::default());
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static.
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let say_hello = move || {
-    ///     // Note that using the `update` methods would be more efficient here.
-    ///     data.try_set_value("Hello, World!".into())
-    /// };
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let reset = move || {
-    ///     // Note that using the `update` methods would be more efficient here.
-    ///     data.try_set_value(Default::default())
-    /// };
-    /// assert_eq!(data.get_value(), "");
-    ///
-    /// // None is returned because the value was able to be updated
-    /// assert_eq!(say_hello(), None);
-    ///
-    /// assert_eq!(data.get_value(), "Hello, World!");
-    ///
-    /// reset();
-    /// assert_eq!(data.get_value(), "");
-    ///
-    /// // You should not call dispose yourself in normal user code.
-    /// // This is shown here for the sake of the example.
-    /// data.dispose();
-    ///
-    /// // The reactive owner is disposed, so the value we intended to set is now
-    /// // returned as some.
-    /// assert_eq!(say_hello().as_deref(), Some("Hello, World!"));
-    /// assert_eq!(reset().as_deref(), Some(""));
-    /// ```
-    pub fn try_set_value(&self, value: T) -> Option<T> {
-        match self.value.try_get_value() {
-            Some(inner) => {
-                *inner.write().or_poisoned() = value;
-                None
-            }
-            None => Some(value),
-        }
-    }
-
-    /// Sets the value within [`StoredValue`].
-    ///
-    /// For types that do not implement [`Clone`], or in cases where allocating the entire object
-    /// would be too expensive, prefer [`StoredValue::update_value`].
-    ///
-    /// # Panics
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_set_value`] for a version without panic.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    ///
-    /// let data = StoredValue::new(10);
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static.
-    /// // *NOTE* this is not the same thing as a derived signal!
-    /// // *NOTE* this will not be automatically rerun as StoredValue is NOT reactive!
-    /// let maxout = move || data.set_value(u8::MAX);
-    /// let zero = move || data.set_value(u8::MIN);
-    ///
-    /// maxout();
-    /// assert_eq!(data.get_value(), u8::MAX);
-    ///
-    /// zero();
-    /// assert_eq!(data.get_value(), u8::MIN);
-    /// ```
-    pub fn set_value(&self, value: T) {
-        self.update_value(|n| *n = value);
+            .and_then(|inner| inner.try_write_value())
     }
 }
 
@@ -380,90 +156,39 @@ impl<T, S> IsDisposed for StoredValue<T, S> {
     }
 }
 
-impl<T, S: Storage<Arc<RwLock<T>>>> StoredValue<T, S>
-where
-    T: Clone + 'static,
-{
-    /// Returns the value within [`StoredValue`] by cloning.
-    ///
-    /// Returns [`Some`] containing the value if the owner of the reactive node has not been
-    /// disposed. When disposed, returns [`None`].
-    ///
-    /// See [`StoredValue::try_with_value`] for a version that avoids cloning. See
-    /// [`StoredValue::get_value`] for a version that clones, but panics if the node is disposed.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    /// # use reactive_graph::traits::Dispose;
-    ///
-    /// // u8 is practically free to clone.
-    /// let data: StoredValue<u8> = StoredValue::new(10);
-    ///
-    /// // Larger data structures can become very expensive to clone.
-    /// // You may prefer to use StoredValue::try_with_value.
-    /// let _expensive: StoredValue<Vec<String>> = StoredValue::new(vec![]);
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static
-    /// let maxout = move || data.set_value(u8::MAX);
-    /// let zero = move || data.set_value(u8::MIN);
-    ///
-    /// maxout();
-    /// assert_eq!(data.try_get_value(), Some(u8::MAX));
-    ///
-    /// zero();
-    /// assert_eq!(data.try_get_value(), Some(u8::MIN));
-    ///
-    /// // You should not call dispose yourself in normal user code.
-    /// // This is shown here for the sake of the example.
-    /// data.dispose();
-    ///
-    /// assert_eq!(data.try_get_value(), None);
-    /// ```
-    pub fn try_get_value(&self) -> Option<T> {
-        self.try_with_value(T::clone)
-    }
-
-    /// Returns the value within [`StoredValue`] by cloning.
-    ///
-    /// See [`StoredValue::with_value`] for a version that avoids cloning.
-    ///
-    /// # Panics
-    /// This function panics when called after the owner of the reactive node has been disposed.
-    /// See [`StoredValue::try_get_value`] for a version without panic.
-    ///
-    /// # Examples
-    /// ```rust
-    /// # use reactive_graph::owner::StoredValue; let owner = reactive_graph::owner::Owner::new(); owner.set();
-    ///
-    /// // u8 is practically free to clone.
-    /// let data: StoredValue<u8> = StoredValue::new(10);
-    ///
-    /// // Larger data structures can become very expensive to clone.
-    /// // You may prefer to use StoredValue::try_with_value.
-    /// let _expensive: StoredValue<Vec<String>> = StoredValue::new(vec![]);
-    ///
-    /// // Easy to move into closures because StoredValue is Copy + 'static
-    /// let maxout = move || data.set_value(u8::MAX);
-    /// let zero = move || data.set_value(u8::MIN);
-    ///
-    /// maxout();
-    /// assert_eq!(data.get_value(), u8::MAX);
-    ///
-    /// zero();
-    /// assert_eq!(data.get_value(), u8::MIN);
-    /// ```
-    pub fn get_value(&self) -> T {
-        self.with_value(T::clone)
-    }
-}
-
 impl<T, S> Dispose for StoredValue<T, S> {
     fn dispose(self) {
         self.value.dispose();
     }
 }
 
+impl<T> From<ArcStoredValue<T>> for StoredValue<T>
+where
+    T: Send + Sync + 'static,
+{
+    #[track_caller]
+    fn from(value: ArcStoredValue<T>) -> Self {
+        StoredValue {
+            #[cfg(debug_assertions)]
+            defined_at: Location::caller(),
+            value: ArenaItem::new(value),
+        }
+    }
+}
+
+impl<T, S> From<StoredValue<T, S>> for ArcStoredValue<T>
+where
+    S: Storage<ArcStoredValue<T>>,
+{
+    #[track_caller]
+    fn from(value: StoredValue<T, S>) -> Self {
+        value
+            .value
+            .try_get_value()
+            .unwrap_or_else(unwrap_signal!(value))
+    }
+}
+
 /// Creates a new [`StoredValue`].
 #[inline(always)]
 #[track_caller]

reactive_graph/src/traits.rs

@@ -52,7 +52,7 @@ use crate::{
     effect::Effect,
     graph::{Observer, Source, Subscriber, ToAnySource},
     owner::Owner,
-    signal::{arc_signal, ArcReadSignal},
+    signal::{arc_signal, guards::UntrackedWriteGuard, ArcReadSignal},
 };
 use any_spawner::Executor;
 use futures::{Stream, StreamExt};
@@ -639,3 +639,189 @@ pub fn panic_getting_disposed_signal(
         )
     }
 }
+
+/// A variation of the [`Read`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait ReadValue: Sized + DefinedAt {
+    /// The guard type that will be returned, which can be dereferenced to the value.
+    type Value: Deref;
+
+    /// Returns the non-reactive guard, or `None` if the value has already been disposed.
+    #[track_caller]
+    fn try_read_value(&self) -> Option<Self::Value>;
+
+    /// Returns the non-reactive guard.
+    ///
+    /// # Panics
+    /// Panics if you try to access a value that has been disposed.
+    #[track_caller]
+    fn read_value(&self) -> Self::Value {
+        self.try_read_value().unwrap_or_else(unwrap_signal!(self))
+    }
+}
+
+/// A variation of the [`With`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait WithValue: DefinedAt {
+    /// The type of the value contained in the value.
+    type Value: ?Sized;
+
+    /// Applies the closure to the value, non-reactively, and returns the result,
+    /// or `None` if the value has already been disposed.
+    #[track_caller]
+    fn try_with_value<U>(
+        &self,
+        fun: impl FnOnce(&Self::Value) -> U,
+    ) -> Option<U>;
+
+    /// Applies the closure to the value, non-reactively, and returns the result.
+    ///
+    /// # Panics
+    /// Panics if you try to access a value that has been disposed.
+    #[track_caller]
+    fn with_value<U>(&self, fun: impl FnOnce(&Self::Value) -> U) -> U {
+        self.try_with_value(fun)
+            .unwrap_or_else(unwrap_signal!(self))
+    }
+}
+
+impl<T> WithValue for T
+where
+    T: DefinedAt + ReadValue,
+{
+    type Value = <<Self as ReadValue>::Value as Deref>::Target;
+
+    fn try_with_value<U>(
+        &self,
+        fun: impl FnOnce(&Self::Value) -> U,
+    ) -> Option<U> {
+        self.try_read_value().map(|value| fun(&value))
+    }
+}
+
+/// A variation of the [`Get`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait GetValue: DefinedAt {
+    /// The type of the value contained in the value.
+    type Value: Clone;
+
+    /// Clones and returns the value of the value, non-reactively,
+    /// or `None` if the value has already been disposed.
+    #[track_caller]
+    fn try_get_value(&self) -> Option<Self::Value>;
+
+    /// Clones and returns the value of the value, non-reactively.
+    ///
+    /// # Panics
+    /// Panics if you try to access a value that has been disposed.
+    #[track_caller]
+    fn get_value(&self) -> Self::Value {
+        self.try_get_value().unwrap_or_else(unwrap_signal!(self))
+    }
+}
+
+impl<T> GetValue for T
+where
+    T: WithValue,
+    T::Value: Clone,
+{
+    type Value = <Self as WithValue>::Value;
+
+    fn try_get_value(&self) -> Option<Self::Value> {
+        self.try_with_value(Self::Value::clone)
+    }
+}
+
+/// A variation of the [`Write`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait WriteValue: Sized + DefinedAt {
+    /// The type of the value's value.
+    type Value: Sized + 'static;
+
+    /// Returns a non-reactive write guard, or `None` if the value has already been disposed.
+    #[track_caller]
+    fn try_write_value(&self) -> Option<UntrackedWriteGuard<Self::Value>>;
+
+    /// Returns a non-reactive write guard.
+    ///
+    /// # Panics
+    /// Panics if you try to access a value that has been disposed.
+    #[track_caller]
+    fn write_value(&self) -> UntrackedWriteGuard<Self::Value> {
+        self.try_write_value().unwrap_or_else(unwrap_signal!(self))
+    }
+}
+
+/// A variation of the [`Update`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait UpdateValue: DefinedAt {
+    /// The type of the value contained in the value.
+    type Value;
+
+    /// Updates the value, returning the value that is
+    /// returned by the update function, or `None` if the value has already been disposed.
+    #[track_caller]
+    fn try_update_value<U>(
+        &self,
+        fun: impl FnOnce(&mut Self::Value) -> U,
+    ) -> Option<U>;
+
+    /// Updates the value.
+    #[track_caller]
+    fn update_value(&self, fun: impl FnOnce(&mut Self::Value)) {
+        self.try_update_value(fun);
+    }
+}
+
+impl<T> UpdateValue for T
+where
+    T: WriteValue,
+{
+    type Value = <Self as WriteValue>::Value;
+
+    #[track_caller]
+    fn try_update_value<U>(
+        &self,
+        fun: impl FnOnce(&mut Self::Value) -> U,
+    ) -> Option<U> {
+        let mut guard = self.try_write_value()?;
+        Some(fun(&mut *guard))
+    }
+}
+
+/// A variation of the [`Set`] trait that provides a signposted "always-non-reactive" API.
+/// E.g. for [`StoredValue`](`crate::owner::StoredValue`).
+pub trait SetValue: DefinedAt {
+    /// The type of the value contained in the value.
+    type Value;
+
+    /// Updates the value by replacing it, non-reactively.
+    ///
+    /// If the value has already been disposed, returns `Some(value)` with the value that was
+    /// passed in. Otherwise, returns `None`.
+    #[track_caller]
+    fn try_set_value(&self, value: Self::Value) -> Option<Self::Value>;
+
+    /// Updates the value by replacing it, non-reactively.
+    #[track_caller]
+    fn set_value(&self, value: Self::Value) {
+        self.try_set_value(value);
+    }
+}
+
+impl<T> SetValue for T
+where
+    T: WriteValue,
+{
+    type Value = <Self as WriteValue>::Value;
+
+    fn try_set_value(&self, value: Self::Value) -> Option<Self::Value> {
+        // Unlike most other traits, for these None actually means success:
+        if let Some(mut guard) = self.try_write_value() {
+            *guard = value;
+            None
+        } else {
+            Some(value)
+        }
+    }
+}

reactive_graph/src/wrappers.rs

@@ -3,15 +3,30 @@
 /// Types that abstract over signals with values that can be read.
 pub mod read {
     use crate::{
-        computed::{ArcMemo, Memo},
+        computed::{ArcMemo, Memo, MemoInner},
         graph::untrack,
-        owner::{ArenaItem, FromLocal, LocalStorage, Storage, SyncStorage},
-        signal::{ArcReadSignal, ArcRwSignal, ReadSignal, RwSignal},
-        traits::{DefinedAt, Dispose, Get, With, WithUntracked},
+        owner::{
+            ArcStoredValue, ArenaItem, FromLocal, LocalStorage, Storage,
+            SyncStorage,
+        },
+        signal::{
+            guards::{Mapped, Plain, ReadGuard},
+            ArcReadSignal, ArcRwSignal, ReadSignal, RwSignal,
+        },
+        traits::{
+            DefinedAt, Dispose, Get, Read, ReadUntracked, ReadValue, Track,
+            With, WithValue,
+        },
         unwrap_signal,
     };
     use send_wrapper::SendWrapper;
-    use std::{panic::Location, sync::Arc};
+    use std::{
+        borrow::Borrow,
+        fmt::Display,
+        ops::Deref,
+        panic::Location,
+        sync::{Arc, RwLock},
+    };
 
     /// Possibilities for the inner type of a [`Signal`].
     pub enum SignalTypes<T, S = SyncStorage>
@@ -24,6 +39,8 @@ pub mod read {
         Memo(ArcMemo<T, S>),
         /// A derived signal.
         DerivedSignal(Arc<dyn Fn() -> T + Send + Sync>),
+        /// A static, stored value.
+        Stored(ArcStoredValue<T>),
     }
 
     impl<T, S> Clone for SignalTypes<T, S>
@@ -35,6 +52,7 @@ pub mod read {
                 Self::ReadSignal(arg0) => Self::ReadSignal(arg0.clone()),
                 Self::Memo(arg0) => Self::Memo(arg0.clone()),
                 Self::DerivedSignal(arg0) => Self::DerivedSignal(arg0.clone()),
+                Self::Stored(arg0) => Self::Stored(arg0.clone()),
             }
         }
     }
@@ -52,6 +70,9 @@ pub mod read {
                 Self::DerivedSignal(_) => {
                     f.debug_tuple("DerivedSignal").finish()
                 }
+                Self::Stored(arg0) => {
+                    f.debug_tuple("Static").field(arg0).finish()
+                }
             }
         }
     }
@@ -168,6 +189,39 @@ pub mod read {
                 defined_at: std::panic::Location::caller(),
             }
         }
+
+        /// Moves a static, nonreactive value into a signal, backed by [`ArcStoredValue`].
+        #[track_caller]
+        pub fn stored(value: T) -> Self {
+            Self {
+                inner: SignalTypes::Stored(ArcStoredValue::new(value)),
+                #[cfg(debug_assertions)]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
+    impl<T, S> ArcSignal<T, S>
+    where
+        S: Storage<T>,
+    {
+        /// Subscribes to this signal in the current reactive scope without doing anything with its value.
+        #[track_caller]
+        pub fn track(&self) {
+            match &self.inner {
+                SignalTypes::ReadSignal(i) => {
+                    i.track();
+                }
+                SignalTypes::Memo(i) => {
+                    i.track();
+                }
+                SignalTypes::DerivedSignal(i) => {
+                    i();
+                }
+                // Doesn't change.
+                SignalTypes::Stored(_) => {}
+            }
+        }
     }
 
     impl<T> Default for ArcSignal<T, SyncStorage>
@@ -175,7 +229,7 @@ pub mod read {
         T: Default + Send + Sync + 'static,
     {
         fn default() -> Self {
-            Self::derive(|| Default::default())
+            Self::stored(Default::default())
         }
     }
 
@@ -231,24 +285,6 @@ pub mod read {
         }
     }
 
-    impl<T, S> WithUntracked for ArcSignal<T, S>
-    where
-        S: Storage<T>,
-    {
-        type Value = T;
-
-        fn try_with_untracked<U>(
-            &self,
-            fun: impl FnOnce(&Self::Value) -> U,
-        ) -> Option<U> {
-            match &self.inner {
-                SignalTypes::ReadSignal(i) => i.try_with_untracked(fun),
-                SignalTypes::Memo(i) => i.try_with_untracked(fun),
-                SignalTypes::DerivedSignal(i) => Some(untrack(|| fun(&i()))),
-            }
-        }
-    }
-
     impl<T, S> With for ArcSignal<T, S>
     where
         S: Storage<T>,
@@ -264,10 +300,63 @@ pub mod read {
                 SignalTypes::ReadSignal(i) => i.try_with(fun),
                 SignalTypes::Memo(i) => i.try_with(fun),
                 SignalTypes::DerivedSignal(i) => Some(fun(&i())),
+                SignalTypes::Stored(i) => i.try_with_value(fun),
             }
         }
     }
 
+    impl<T, S> ReadUntracked for ArcSignal<T, S>
+    where
+        S: Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read_untracked(&self) -> Option<Self::Value> {
+            match &self.inner {
+                SignalTypes::ReadSignal(i) => {
+                    i.try_read_untracked().map(SignalReadGuard::Read)
+                }
+                SignalTypes::Memo(i) => {
+                    i.try_read_untracked().map(SignalReadGuard::Memo)
+                }
+                SignalTypes::DerivedSignal(i) => {
+                    Some(SignalReadGuard::Owned(untrack(|| i())))
+                }
+                SignalTypes::Stored(i) => {
+                    i.try_read_value().map(SignalReadGuard::Read)
+                }
+            }
+            .map(ReadGuard::new)
+        }
+    }
+
+    impl<T, S> Read for ArcSignal<T, S>
+    where
+        S: Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read(&self) -> Option<Self::Value> {
+            match &self.inner {
+                SignalTypes::ReadSignal(i) => {
+                    i.try_read().map(SignalReadGuard::Read)
+                }
+                SignalTypes::Memo(i) => i.try_read().map(SignalReadGuard::Memo),
+                SignalTypes::DerivedSignal(i) => {
+                    Some(SignalReadGuard::Owned(i()))
+                }
+                SignalTypes::Stored(i) => {
+                    i.try_read_value().map(SignalReadGuard::Read)
+                }
+            }
+            .map(ReadGuard::new)
+        }
+
+        fn read(&self) -> Self::Value {
+            self.try_read().unwrap_or_else(unwrap_signal!(self))
+        }
+    }
+
     /// A wrapper for any kind of arena-allocated reactive signal:
     /// an [`ReadSignal`], [`Memo`], [`RwSignal`], or derived signal closure.
     ///
@@ -343,31 +432,6 @@ pub mod read {
         }
     }
 
-    impl<T, S> WithUntracked for Signal<T, S>
-    where
-        T: 'static,
-        S: Storage<SignalTypes<T, S>> + Storage<T>,
-    {
-        type Value = T;
-
-        fn try_with_untracked<U>(
-            &self,
-            fun: impl FnOnce(&Self::Value) -> U,
-        ) -> Option<U> {
-            self.inner
-                // clone the inner Arc type and release the lock
-                // prevents deadlocking if the derived value includes taking a lock on the arena
-                .try_with_value(Clone::clone)
-                .and_then(|inner| match &inner {
-                    SignalTypes::ReadSignal(i) => i.try_with_untracked(fun),
-                    SignalTypes::Memo(i) => i.try_with_untracked(fun),
-                    SignalTypes::DerivedSignal(i) => {
-                        Some(untrack(|| fun(&i())))
-                    }
-                })
-        }
-    }
-
     impl<T, S> With for Signal<T, S>
     where
         T: 'static,
@@ -387,10 +451,79 @@ pub mod read {
                     SignalTypes::ReadSignal(i) => i.try_with(fun),
                     SignalTypes::Memo(i) => i.try_with(fun),
                     SignalTypes::DerivedSignal(i) => Some(fun(&i())),
+                    SignalTypes::Stored(i) => i.try_with_value(fun),
                 })
         }
     }
 
+    impl<T, S> ReadUntracked for Signal<T, S>
+    where
+        T: 'static,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read_untracked(&self) -> Option<Self::Value> {
+            self.inner
+                // clone the inner Arc type and release the lock
+                // prevents deadlocking if the derived value includes taking a lock on the arena
+                .try_with_value(Clone::clone)
+                .and_then(|inner| {
+                    match &inner {
+                        SignalTypes::ReadSignal(i) => {
+                            i.try_read_untracked().map(SignalReadGuard::Read)
+                        }
+                        SignalTypes::Memo(i) => {
+                            i.try_read_untracked().map(SignalReadGuard::Memo)
+                        }
+                        SignalTypes::DerivedSignal(i) => {
+                            Some(SignalReadGuard::Owned(untrack(|| i())))
+                        }
+                        SignalTypes::Stored(i) => {
+                            i.try_read_value().map(SignalReadGuard::Read)
+                        }
+                    }
+                    .map(ReadGuard::new)
+                })
+        }
+    }
+
+    impl<T, S> Read for Signal<T, S>
+    where
+        T: 'static,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read(&self) -> Option<Self::Value> {
+            self.inner
+                // clone the inner Arc type and release the lock
+                // prevents deadlocking if the derived value includes taking a lock on the arena
+                .try_with_value(Clone::clone)
+                .and_then(|inner| {
+                    match &inner {
+                        SignalTypes::ReadSignal(i) => {
+                            i.try_read().map(SignalReadGuard::Read)
+                        }
+                        SignalTypes::Memo(i) => {
+                            i.try_read().map(SignalReadGuard::Memo)
+                        }
+                        SignalTypes::DerivedSignal(i) => {
+                            Some(SignalReadGuard::Owned(i()))
+                        }
+                        SignalTypes::Stored(i) => {
+                            i.try_read_value().map(SignalReadGuard::Read)
+                        }
+                    }
+                    .map(ReadGuard::new)
+                })
+        }
+
+        fn read(&self) -> Self::Value {
+            self.try_read().unwrap_or_else(unwrap_signal!(self))
+        }
+    }
+
     impl<T> Signal<T>
     where
         T: Send + Sync + 'static,
@@ -433,6 +566,18 @@ pub mod read {
                 defined_at: std::panic::Location::caller(),
             }
         }
+
+        /// Moves a static, nonreactive value into a signal, backed by [`ArcStoredValue`].
+        #[track_caller]
+        pub fn stored(value: T) -> Self {
+            Self {
+                inner: ArenaItem::new_with_storage(SignalTypes::Stored(
+                    ArcStoredValue::new(value),
+                )),
+                #[cfg(debug_assertions)]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
     }
 
     impl<T> Signal<T, LocalStorage>
@@ -460,6 +605,49 @@ pub mod read {
                 defined_at: std::panic::Location::caller(),
             }
         }
+
+        /// Moves a static, nonreactive value into a signal, backed by [`ArcStoredValue`].
+        /// Works like [`Signal::stored`] but uses [`LocalStorage`].
+        #[track_caller]
+        pub fn stored_local(value: T) -> Self {
+            Self {
+                inner: ArenaItem::new_local(SignalTypes::Stored(
+                    ArcStoredValue::new(value),
+                )),
+                #[cfg(debug_assertions)]
+                defined_at: std::panic::Location::caller(),
+            }
+        }
+    }
+
+    impl<T, S> Signal<T, S>
+    where
+        T: 'static,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        /// Subscribes to this signal in the current reactive scope without doing anything with its value.
+        #[track_caller]
+        pub fn track(&self) {
+            let inner = self
+                .inner
+                // clone the inner Arc type and release the lock
+                // prevents deadlocking if the derived value includes taking a lock on the arena
+                .try_with_value(Clone::clone)
+                .unwrap_or_else(unwrap_signal!(self));
+            match inner {
+                SignalTypes::ReadSignal(i) => {
+                    i.track();
+                }
+                SignalTypes::Memo(i) => {
+                    i.track();
+                }
+                SignalTypes::DerivedSignal(i) => {
+                    i();
+                }
+                // Doesn't change.
+                SignalTypes::Stored(_) => {}
+            }
+        }
     }
 
     impl<T> Default for Signal<T>
@@ -467,7 +655,7 @@ pub mod read {
         T: Send + Sync + Default + 'static,
     {
         fn default() -> Self {
-            Self::derive(|| Default::default())
+            Self::stored(Default::default())
         }
     }
 
@@ -476,34 +664,34 @@ pub mod read {
         T: Default + 'static,
     {
         fn default() -> Self {
-            Self::derive_local(|| Default::default())
+            Self::stored_local(Default::default())
         }
     }
 
-    impl<T: Clone + Send + Sync + 'static> From<T> for ArcSignal<T, SyncStorage> {
+    impl<T: Send + Sync + 'static> From<T> for ArcSignal<T, SyncStorage> {
         #[track_caller]
         fn from(value: T) -> Self {
-            Self::derive(move || value.clone())
+            ArcSignal::stored(value)
         }
     }
 
     impl<T> From<T> for Signal<T>
     where
-        T: Clone + Send + Sync + 'static,
+        T: Send + Sync + 'static,
     {
         #[track_caller]
         fn from(value: T) -> Self {
-            Self::derive(move || value.clone())
+            Self::stored(value)
         }
     }
 
     impl<T> From<T> for Signal<T, LocalStorage>
     where
-        T: Clone + 'static,
+        T: 'static,
     {
         #[track_caller]
         fn from(value: T) -> Self {
-            Self::derive_local(move || value.clone())
+            Self::stored_local(value)
         }
     }
 
@@ -715,23 +903,6 @@ pub mod read {
         }
     }
 
-    impl<T, S> WithUntracked for MaybeSignal<T, S>
-    where
-        S: Storage<SignalTypes<T, S>> + Storage<T>,
-    {
-        type Value = T;
-
-        fn try_with_untracked<U>(
-            &self,
-            fun: impl FnOnce(&Self::Value) -> U,
-        ) -> Option<U> {
-            match self {
-                Self::Static(t) => Some(fun(t)),
-                Self::Dynamic(s) => s.try_with_untracked(fun),
-            }
-        }
-    }
-
     impl<T, S> With for MaybeSignal<T, S>
     where
         T: Send + Sync + 'static,
@@ -750,6 +921,44 @@ pub mod read {
         }
     }
 
+    impl<T, S> ReadUntracked for MaybeSignal<T, S>
+    where
+        T: Clone,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read_untracked(&self) -> Option<Self::Value> {
+            match self {
+                Self::Static(t) => {
+                    Some(ReadGuard::new(SignalReadGuard::Owned(t.clone())))
+                }
+                Self::Dynamic(s) => s.try_read_untracked(),
+            }
+        }
+    }
+
+    impl<T, S> Read for MaybeSignal<T, S>
+    where
+        T: Clone,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        type Value = ReadGuard<T, SignalReadGuard<T, S>>;
+
+        fn try_read(&self) -> Option<Self::Value> {
+            match self {
+                Self::Static(t) => {
+                    Some(ReadGuard::new(SignalReadGuard::Owned(t.clone())))
+                }
+                Self::Dynamic(s) => s.try_read(),
+            }
+        }
+
+        fn read(&self) -> Self::Value {
+            self.try_read().unwrap_or_else(unwrap_signal!(self))
+        }
+    }
+
     impl<T> MaybeSignal<T>
     where
         T: Send + Sync,
@@ -771,6 +980,21 @@ pub mod read {
         }
     }
 
+    impl<T, S> MaybeSignal<T, S>
+    where
+        T: 'static,
+        S: Storage<SignalTypes<T, S>> + Storage<T>,
+    {
+        /// Subscribes to this signal in the current reactive scope without doing anything with its value.
+        #[track_caller]
+        pub fn track(&self) {
+            match self {
+                Self::Static(_) => {}
+                Self::Dynamic(signal) => signal.track(),
+            }
+        }
+    }
+
     impl<T> From<T> for MaybeSignal<T, SyncStorage>
     where
         SyncStorage: Storage<T>,
@@ -893,7 +1117,7 @@ pub mod read {
 
     impl<S> From<&str> for MaybeSignal<String, S>
     where
-        S: Storage<String>,
+        S: Storage<String> + Storage<Arc<RwLock<String>>>,
     {
         fn from(value: &str) -> Self {
             Self::Static(value.to_string())
@@ -968,23 +1192,6 @@ pub mod read {
         }
     }
 
-    impl<T, S> WithUntracked for MaybeProp<T, S>
-    where
-        S: Storage<SignalTypes<Option<T>, S>> + Storage<Option<T>>,
-    {
-        type Value = Option<T>;
-
-        fn try_with_untracked<U>(
-            &self,
-            fun: impl FnOnce(&Self::Value) -> U,
-        ) -> Option<U> {
-            match &self.0 {
-                None => Some(fun(&None)),
-                Some(inner) => inner.try_with_untracked(fun),
-            }
-        }
-    }
-
     impl<T, S> With for MaybeProp<T, S>
     where
         T: Send + Sync + 'static,
@@ -1003,6 +1210,40 @@ pub mod read {
         }
     }
 
+    impl<T, S> ReadUntracked for MaybeProp<T, S>
+    where
+        T: Clone,
+        S: Storage<SignalTypes<Option<T>, S>> + Storage<Option<T>>,
+    {
+        type Value = ReadGuard<Option<T>, SignalReadGuard<Option<T>, S>>;
+
+        fn try_read_untracked(&self) -> Option<Self::Value> {
+            match &self.0 {
+                None => Some(ReadGuard::new(SignalReadGuard::Owned(None))),
+                Some(inner) => inner.try_read_untracked(),
+            }
+        }
+    }
+
+    impl<T, S> Read for MaybeProp<T, S>
+    where
+        T: Clone,
+        S: Storage<SignalTypes<Option<T>, S>> + Storage<Option<T>>,
+    {
+        type Value = ReadGuard<Option<T>, SignalReadGuard<Option<T>, S>>;
+
+        fn try_read(&self) -> Option<Self::Value> {
+            match &self.0 {
+                None => Some(ReadGuard::new(SignalReadGuard::Owned(None))),
+                Some(inner) => inner.try_read(),
+            }
+        }
+
+        fn read(&self) -> Self::Value {
+            self.try_read().unwrap_or_else(unwrap_signal!(self))
+        }
+    }
+
     impl<T> MaybeProp<T>
     where
         T: Send + Sync,
@@ -1016,6 +1257,21 @@ pub mod read {
         }
     }
 
+    impl<T, S> MaybeProp<T, S>
+    where
+        T: 'static,
+        S: Storage<SignalTypes<Option<T>, S>> + Storage<Option<T>>,
+    {
+        /// Subscribes to this signal in the current reactive scope without doing anything with its value.
+        #[track_caller]
+        pub fn track(&self) {
+            match &self.0 {
+                None => {}
+                Some(signal) => signal.track(),
+            }
+        }
+    }
+
     impl<T> From<T> for MaybeProp<T>
     where
         SyncStorage: Storage<Option<T>>,
@@ -1242,6 +1498,76 @@ pub mod read {
             Self(Some(MaybeSignal::from_local(Some(value.to_string()))))
         }
     }
+
+    /// The content of a [`Signal`] wrapper read guard, variable depending on the signal type.
+    #[derive(Debug)]
+    pub enum SignalReadGuard<T: 'static, S: Storage<T>> {
+        /// A read signal guard.
+        Read(ReadGuard<T, Plain<T>>),
+        /// A memo guard.
+        Memo(ReadGuard<T, Mapped<Plain<MemoInner<T, S>>, T>>),
+        /// A fake guard for derived signals, the content had to actually be cloned, so it's not a guard but we pretend it is.
+        Owned(T),
+    }
+
+    impl<T, S> Clone for SignalReadGuard<T, S>
+    where
+        S: Storage<T>,
+        T: Clone,
+        Plain<T>: Clone,
+        Mapped<Plain<MemoInner<T, S>>, T>: Clone,
+    {
+        fn clone(&self) -> Self {
+            match self {
+                SignalReadGuard::Read(i) => SignalReadGuard::Read(i.clone()),
+                SignalReadGuard::Memo(i) => SignalReadGuard::Memo(i.clone()),
+                SignalReadGuard::Owned(i) => SignalReadGuard::Owned(i.clone()),
+            }
+        }
+    }
+
+    impl<T, S> Deref for SignalReadGuard<T, S>
+    where
+        S: Storage<T>,
+    {
+        type Target = T;
+        fn deref(&self) -> &Self::Target {
+            match self {
+                SignalReadGuard::Read(i) => i,
+                SignalReadGuard::Memo(i) => i,
+                SignalReadGuard::Owned(i) => i,
+            }
+        }
+    }
+
+    impl<T, S> Borrow<T> for SignalReadGuard<T, S>
+    where
+        S: Storage<T>,
+    {
+        fn borrow(&self) -> &T {
+            self.deref()
+        }
+    }
+
+    impl<T, S> PartialEq<T> for SignalReadGuard<T, S>
+    where
+        S: Storage<T>,
+        T: PartialEq,
+    {
+        fn eq(&self, other: &T) -> bool {
+            self.deref() == other
+        }
+    }
+
+    impl<T, S> Display for SignalReadGuard<T, S>
+    where
+        S: Storage<T>,
+        T: Display,
+    {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            Display::fmt(&**self, f)
+        }
+    }
 }
 
 /// Types that abstract over the ability to update a signal.

reactive_graph/tests/cleanup.rs

@@ -0,0 +1,88 @@
+use reactive_graph::{
+    computed::Memo,
+    owner::{on_cleanup, Owner},
+    signal::{RwSignal, Trigger},
+    traits::{Dispose, GetUntracked, Track},
+};
+use std::sync::Arc;
+
+#[test]
+fn cleanup_on_dispose() {
+    let owner = Owner::new();
+    owner.set();
+
+    struct ExecuteOnDrop(Option<Box<dyn FnOnce() + Send + Sync>>);
+
+    impl ExecuteOnDrop {
+        fn new(f: impl FnOnce() + Send + Sync + 'static) -> Self {
+            Self(Some(Box::new(f)))
+        }
+    }
+    impl Drop for ExecuteOnDrop {
+        fn drop(&mut self) {
+            self.0.take().unwrap()();
+        }
+    }
+
+    let trigger = Trigger::new();
+
+    println!("STARTING");
+
+    let memo = Memo::new(move |_| {
+        trigger.track();
+
+        // An example of why you might want to do this is that
+        // when something goes out of reactive scope you want it to be cleaned up.
+        // The cleaning up might have side effects, and those side effects might cause
+        // re-renders where new `on_cleanup` are registered.
+        let on_drop = ExecuteOnDrop::new(|| {
+            on_cleanup(|| println!("Nested cleanup in progress."))
+        });
+
+        on_cleanup(move || {
+            println!("Cleanup in progress.");
+            drop(on_drop)
+        });
+    });
+    println!("Memo 1: {:?}", memo);
+    memo.get_untracked(); // First cleanup registered.
+
+    memo.dispose(); // Cleanup not run here.
+
+    println!("Cleanup should have been executed.");
+
+    let memo = Memo::new(move |_| {
+        // New cleanup registered. It'll panic here.
+        on_cleanup(move || println!("Test passed."));
+    });
+    println!("Memo 2: {:?}", memo);
+    println!("^ Note how the memos have the same key (different versions).");
+    memo.get_untracked(); // First cleanup registered.
+
+    println!("Test passed.");
+
+    memo.dispose();
+}
+
+#[test]
+fn leak_on_dispose() {
+    let owner = Owner::new();
+    owner.set();
+
+    let trigger = Trigger::new();
+
+    let value = Arc::new(());
+    let weak = Arc::downgrade(&value);
+
+    let memo = Memo::new(move |_| {
+        trigger.track();
+
+        RwSignal::new(value.clone());
+    });
+
+    memo.get_untracked();
+
+    memo.dispose();
+
+    assert!(weak.upgrade().is_none()); // Should have been dropped.
+}

reactive_stores/src/lib.rs

@@ -171,12 +171,26 @@ impl KeyMap {
     where
         K: Debug + Hash + PartialEq + Eq + Send + Sync + 'static,
     {
+        // this incredibly defensive mechanism takes the guard twice
+        // on initialization. unfortunately, this is because `initialize`, on
+        // a nested keyed field can, when being initialized), can in fact try
+        // to take the lock again, as we try to insert the keys of the parent
+        // while inserting the keys on this child.
+        //
+        // see here https://github.com/leptos-rs/leptos/issues/3086
         let mut guard = self.0.write().or_poisoned();
-        let entry = guard
-            .entry(path)
-            .or_insert_with(|| Box::new(FieldKeys::new(initialize())));
-        let entry = entry.downcast_mut::<FieldKeys<K>>()?;
-        Some(fun(entry))
+        if guard.contains_key(&path) {
+            let entry = guard.get_mut(&path)?;
+            let entry = entry.downcast_mut::<FieldKeys<K>>()?;
+            Some(fun(entry))
+        } else {
+            drop(guard);
+            let keys = Box::new(FieldKeys::new(initialize()));
+            let mut guard = self.0.write().or_poisoned();
+            let entry = guard.entry(path).or_insert(keys);
+            let entry = entry.downcast_mut::<FieldKeys<K>>()?;
+            Some(fun(entry))
+        }
     }
 }
 

router/src/components.rs

@@ -24,6 +24,7 @@ use reactive_graph::{
 use std::{
     borrow::Cow,
     fmt::{Debug, Display},
+    mem,
     sync::Arc,
     time::Duration,
 };
@@ -47,7 +48,7 @@ where
     }
 }
 
-#[component]
+#[component(transparent)]
 pub fn Router<Chil>(
     /// The base URL for the router. Defaults to `""`.
     #[prop(optional, into)]
@@ -101,6 +102,7 @@ where
         location,
         state,
         set_is_routing,
+        query_mutations: Default::default(),
     });
 
     let children = children.into_inner();
@@ -114,6 +116,8 @@ pub(crate) struct RouterContext {
     pub location: Location,
     pub state: ArcRwSignal<State>,
     pub set_is_routing: Option<SignalSetter<bool>>,
+    pub query_mutations:
+        ArcStoredValue<Vec<(Oco<'static, str>, Option<String>)>>,
 }
 
 impl RouterContext {
@@ -130,7 +134,7 @@ impl RouterContext {
             resolve_path("", path, None)
         };
 
-        let url = match resolved_to.map(|to| BrowserUrl::parse(&to)) {
+        let mut url = match resolved_to.map(|to| BrowserUrl::parse(&to)) {
             Some(Ok(url)) => url,
             Some(Err(e)) => {
                 leptos::logging::error!("Error parsing URL: {e:?}");
@@ -141,6 +145,22 @@ impl RouterContext {
                 return;
             }
         };
+        let query_mutations =
+            mem::take(&mut *self.query_mutations.write_value());
+        if !query_mutations.is_empty() {
+            for (key, value) in query_mutations {
+                if let Some(value) = value {
+                    url.search_params_mut().replace(key, value);
+                } else {
+                    url.search_params_mut().remove(&key);
+                }
+            }
+            *url.search_mut() = url
+                .search_params()
+                .to_query_string()
+                .trim_start_matches('?')
+                .into()
+        }
 
         if url.origin() != current.origin() {
             window().location().set_href(path).unwrap();
@@ -153,13 +173,14 @@ impl RouterContext {
         }
 
         // update URL signal, if necessary
+        let value = url.to_full_path();
         if current != url {
             drop(current);
             self.current_url.set(url);
         }
 
         BrowserUrl::complete_navigation(&LocationChange {
-            value: path.to_string(),
+            value,
             replace: options.replace,
             scroll: options.scroll,
             state: options.state,
@@ -204,7 +225,7 @@ where
     }
 }*/
 
-#[component]
+#[component(transparent)]
 pub fn Routes<Defs, FallbackFn, Fallback>(
     fallback: FallbackFn,
     children: RouteChildren<Defs>,
@@ -247,7 +268,7 @@ where
     }
 }
 
-#[component]
+#[component(transparent)]
 pub fn FlatRoutes<Defs, FallbackFn, Fallback>(
     fallback: FallbackFn,
     children: RouteChildren<Defs>,
@@ -294,7 +315,7 @@ where
     }
 }
 
-#[component]
+#[component(transparent)]
 pub fn Route<Segments, View>(
     path: Segments,
     view: View,
@@ -306,7 +327,7 @@ where
     NestedRoute::new(path, view).ssr_mode(ssr)
 }
 
-#[component]
+#[component(transparent)]
 pub fn ParentRoute<Segments, View, Children>(
     path: Segments,
     view: View,
@@ -320,7 +341,7 @@ where
     NestedRoute::new(path, view).ssr_mode(ssr).child(children)
 }
 
-#[component]
+#[component(transparent)]
 pub fn ProtectedRoute<Segments, ViewFn, View, C, PathFn, P>(
     path: Segments,
     view: ViewFn,
@@ -362,7 +383,7 @@ where
     NestedRoute::new(path, view).ssr_mode(ssr)
 }
 
-#[component]
+#[component(transparent)]
 pub fn ProtectedParentRoute<Segments, ViewFn, View, C, PathFn, P, Children>(
     path: Segments,
     view: ViewFn,
@@ -424,7 +445,7 @@ where
 ///
 /// [`leptos_actix`]: <https://docs.rs/leptos_actix/>
 /// [`leptos_axum`]: <https://docs.rs/leptos_axum/>
-#[component]
+#[component(transparent)]
 pub fn Redirect<P>(
     /// The relative path to which the user should be redirected.
     path: P,

router/src/hooks.rs

@@ -4,15 +4,18 @@ use crate::{
     navigate::NavigateOptions,
     params::{Params, ParamsError, ParamsMap},
 };
-use leptos::oco::Oco;
+use leptos::{leptos_dom::helpers::request_animation_frame, oco::Oco};
 use reactive_graph::{
     computed::{ArcMemo, Memo},
-    owner::use_context,
+    owner::{expect_context, use_context},
     signal::{ArcRwSignal, ReadSignal},
-    traits::{Get, GetUntracked, With},
+    traits::{Get, GetUntracked, ReadUntracked, With, WriteValue},
     wrappers::write::SignalSetter,
 };
-use std::str::FromStr;
+use std::{
+    str::FromStr,
+    sync::atomic::{AtomicBool, Ordering},
+};
 
 #[track_caller]
 #[deprecated = "This has been renamed to `query_signal` to match Rust naming \
@@ -93,10 +96,15 @@ pub fn query_signal_with_options<T>(
 where
     T: FromStr + ToString + PartialEq + Send + Sync,
 {
+    static IS_NAVIGATING: AtomicBool = AtomicBool::new(false);
+
     let mut key: Oco<'static, str> = key.into();
     let query_map = use_query_map();
     let navigate = use_navigate();
     let location = use_location();
+    let RouterContext {
+        query_mutations, ..
+    } = expect_context();
 
     let get = Memo::new({
         let key = key.clone_inplace();
@@ -108,20 +116,25 @@ where
     });
 
     let set = SignalSetter::map(move |value: Option<T>| {
-        let mut new_query_map = query_map.get();
-        match value {
-            Some(value) => {
-                new_query_map.insert(key.to_string(), value.to_string());
-            }
-            None => {
-                new_query_map.remove(&key);
-            }
-        }
-        let qs = new_query_map.to_query_string();
         let path = location.pathname.get_untracked();
         let hash = location.hash.get_untracked();
+        let qs = location.query.read_untracked().to_query_string();
         let new_url = format!("{path}{qs}{hash}");
-        navigate(&new_url, nav_options.clone());
+        query_mutations
+            .write_value()
+            .push((key.clone(), value.as_ref().map(ToString::to_string)));
+
+        if !IS_NAVIGATING.load(Ordering::Relaxed) {
+            IS_NAVIGATING.store(true, Ordering::Relaxed);
+            request_animation_frame({
+                let navigate = navigate.clone();
+                let nav_options = nav_options.clone();
+                move || {
+                    navigate(&new_url, nav_options.clone());
+                    IS_NAVIGATING.store(false, Ordering::Relaxed)
+                }
+            })
+        }
     });
 
     (get, set)

router/src/location/history.rs

@@ -121,7 +121,7 @@ impl LocationProvider for BrowserUrl {
                         && curr.path() == new_url.path()
                 };
 
-                url.set(new_url);
+                url.set(new_url.clone());
                 if same_path {
                     Self::complete_navigation(&loc);
                 }
@@ -130,12 +130,19 @@ impl LocationProvider for BrowserUrl {
                 if !same_path {
                     *pending.lock().or_poisoned() = Some(tx);
                 }
+                let url = url.clone();
                 async move {
                     if !same_path {
                         // if it has been canceled, ignore
                         // otherwise, complete navigation -- i.e., set URL in address bar
                         if rx.await.is_ok() {
-                            Self::complete_navigation(&loc);
+                            // only update the URL in the browser if this is still the current URL
+                            // if we've navigated to another page in the meantime, don't update the
+                            // browser URL
+                            let curr = url.read_untracked();
+                            if curr == new_url {
+                                Self::complete_navigation(&loc);
+                            }
                         }
                     }
                 }

router/src/location/mod.rs

@@ -36,22 +36,42 @@ impl Url {
         &self.origin
     }
 
+    pub fn origin_mut(&mut self) -> &mut String {
+        &mut self.origin
+    }
+
     pub fn path(&self) -> &str {
         &self.path
     }
 
+    pub fn path_mut(&mut self) -> &mut str {
+        &mut self.path
+    }
+
     pub fn search(&self) -> &str {
         &self.search
     }
 
+    pub fn search_mut(&mut self) -> &mut String {
+        &mut self.search
+    }
+
     pub fn search_params(&self) -> &ParamsMap {
         &self.search_params
     }
 
+    pub fn search_params_mut(&mut self) -> &mut ParamsMap {
+        &mut self.search_params
+    }
+
     pub fn hash(&self) -> &str {
         &self.hash
     }
 
+    pub fn hash_mut(&mut self) -> &mut String {
+        &mut self.hash
+    }
+
     pub fn provide_server_action_error(&self) {
         let search_params = self.search_params();
         if let (Some(err), Some(path)) = (
@@ -62,6 +82,19 @@ impl Url {
         }
     }
 
+    pub(crate) fn to_full_path(&self) -> String {
+        let mut path = self.path.to_string();
+        if !self.search.is_empty() {
+            path.push('?');
+            path.push_str(&self.search);
+        }
+        if !self.hash.is_empty() {
+            path.push('#');
+            path.push_str(&self.hash);
+        }
+        path
+    }
+
     pub fn escape(s: &str) -> String {
         #[cfg(not(feature = "ssr"))]
         {

router/src/params.rs

@@ -21,6 +21,9 @@ impl ParamsMap {
     }
 
     /// Inserts a value into the map.
+    ///
+    /// If a value with that key already exists, the new value will be added to it.
+    /// To replace the value instead, see [`replace`].
     pub fn insert(&mut self, key: impl Into<Cow<'static, str>>, value: String) {
         let value = unescape(&value);
 
@@ -32,6 +35,23 @@ impl ParamsMap {
         }
     }
 
+    /// Inserts a value into the map, replacing any existing value for that key.
+    pub fn replace(
+        &mut self,
+        key: impl Into<Cow<'static, str>>,
+        value: String,
+    ) {
+        let value = unescape(&value);
+
+        let key = key.into();
+        if let Some(prev) = self.0.iter_mut().find(|(k, _)| k == &key) {
+            prev.1.clear();
+            prev.1.push(value);
+        } else {
+            self.0.push((key, vec![value]));
+        }
+    }
+
     /// Gets the most-recently-added value of this param from the map.
     pub fn get(&self, key: &str) -> Option<String> {
         self.get_str(key).map(ToOwned::to_owned)

tachys/src/html/attribute/any_attribute.rs

@@ -67,107 +67,121 @@ where
 
         let value = Box::new(self) as Box<dyn Any + Send>;
 
-        #[cfg(feature = "ssr")]
-        let to_html = |value: Box<dyn Any>,
-                       buf: &mut String,
-                       class: &mut String,
-                       style: &mut String,
-                       inner_html: &mut String| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyAttribute::to_html could not be downcast");
-            value.to_html(buf, class, style, inner_html);
-        };
-        let build = |value: Box<dyn Any>,
+        match value.downcast::<AnyAttribute>() {
+            // if it's already an AnyAttribute, we don't need to double-wrap it
+            Ok(any_attribute) => *any_attribute,
+            Err(value) => {
+                #[cfg(feature = "ssr")]
+                let to_html =
+                    |value: Box<dyn Any>,
+                     buf: &mut String,
+                     class: &mut String,
+                     style: &mut String,
+                     inner_html: &mut String| {
+                        let value = value.downcast::<T>().expect(
+                            "AnyAttribute::to_html could not be downcast",
+                        );
+                        value.to_html(buf, class, style, inner_html);
+                    };
+                let build =
+                    |value: Box<dyn Any>,
                      el: &crate::renderer::types::Element| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyAttribute::build couldn't downcast");
-            let state = Box::new(value.build(el));
+                        let value = value
+                            .downcast::<T>()
+                            .expect("AnyAttribute::build couldn't downcast");
+                        let state = Box::new(value.build(el));
 
-            AnyAttributeState {
-                type_id: TypeId::of::<T>(),
-                state,
-                el: el.clone(),
-            }
-        };
-        #[cfg(feature = "hydrate")]
-        let hydrate_from_server =
-            |value: Box<dyn Any>, el: &crate::renderer::types::Element| {
-                let value = value.downcast::<T>().expect(
-                    "AnyAttribute::hydrate_from_server couldn't downcast",
-                );
-                let state = Box::new(value.hydrate::<true>(el));
+                        AnyAttributeState {
+                            type_id: TypeId::of::<T>(),
+                            state,
+                            el: el.clone(),
+                        }
+                    };
+                #[cfg(feature = "hydrate")]
+                let hydrate_from_server =
+                    |value: Box<dyn Any>,
+                     el: &crate::renderer::types::Element| {
+                        let value = value.downcast::<T>().expect(
+                            "AnyAttribute::hydrate_from_server couldn't \
+                             downcast",
+                        );
+                        let state = Box::new(value.hydrate::<true>(el));
 
-                AnyAttributeState {
+                        AnyAttributeState {
+                            type_id: TypeId::of::<T>(),
+                            state,
+                            el: el.clone(),
+                        }
+                    };
+                #[cfg(feature = "hydrate")]
+                let hydrate_from_template =
+                    |value: Box<dyn Any>,
+                     el: &crate::renderer::types::Element| {
+                        let value = value.downcast::<T>().expect(
+                            "AnyAttribute::hydrate_from_server couldn't \
+                             downcast",
+                        );
+                        let state = Box::new(value.hydrate::<true>(el));
+
+                        AnyAttributeState {
+                            type_id: TypeId::of::<T>(),
+                            state,
+                            el: el.clone(),
+                        }
+                    };
+                let rebuild =
+                    |new_type_id: TypeId,
+                     value: Box<dyn Any>,
+                     state: &mut AnyAttributeState| {
+                        let value = value.downcast::<T>().expect(
+                            "AnyAttribute::rebuild couldn't downcast value",
+                        );
+                        if new_type_id == state.type_id {
+                            let state = state.state.downcast_mut().expect(
+                                "AnyAttribute::rebuild couldn't downcast state",
+                            );
+                            value.rebuild(state);
+                        } else {
+                            let new = value.into_any_attr().build(&state.el);
+                            *state = new;
+                        }
+                    };
+                #[cfg(feature = "ssr")]
+                let dry_resolve = |value: &mut Box<dyn Any + Send>| {
+                    let value = value
+                        .downcast_mut::<T>()
+                        .expect("AnyView::resolve could not be downcast");
+                    value.dry_resolve();
+                };
+
+                #[cfg(feature = "ssr")]
+                let resolve = |value: Box<dyn Any>| {
+                    let value = value
+                        .downcast::<T>()
+                        .expect("AnyView::resolve could not be downcast");
+                    Box::pin(
+                        async move { value.resolve().await.into_any_attr() },
+                    )
+                        as Pin<Box<dyn Future<Output = AnyAttribute> + Send>>
+                };
+                AnyAttribute {
                     type_id: TypeId::of::<T>(),
-                    state,
-                    el: el.clone(),
+                    html_len,
+                    value,
+                    #[cfg(feature = "ssr")]
+                    to_html,
+                    build,
+                    rebuild,
+                    #[cfg(feature = "hydrate")]
+                    hydrate_from_server,
+                    #[cfg(feature = "hydrate")]
+                    hydrate_from_template,
+                    #[cfg(feature = "ssr")]
+                    resolve,
+                    #[cfg(feature = "ssr")]
+                    dry_resolve,
                 }
-            };
-        #[cfg(feature = "hydrate")]
-        let hydrate_from_template =
-            |value: Box<dyn Any>, el: &crate::renderer::types::Element| {
-                let value = value.downcast::<T>().expect(
-                    "AnyAttribute::hydrate_from_server couldn't downcast",
-                );
-                let state = Box::new(value.hydrate::<true>(el));
-
-                AnyAttributeState {
-                    type_id: TypeId::of::<T>(),
-                    state,
-                    el: el.clone(),
-                }
-            };
-        let rebuild = |new_type_id: TypeId,
-                       value: Box<dyn Any>,
-                       state: &mut AnyAttributeState| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyAttribute::rebuild couldn't downcast value");
-            if new_type_id == state.type_id {
-                let state = state
-                    .state
-                    .downcast_mut()
-                    .expect("AnyAttribute::rebuild couldn't downcast state");
-                value.rebuild(state);
-            } else {
-                let new = value.into_any_attr().build(&state.el);
-                *state = new;
             }
-        };
-        #[cfg(feature = "ssr")]
-        let dry_resolve = |value: &mut Box<dyn Any + Send>| {
-            let value = value
-                .downcast_mut::<T>()
-                .expect("AnyView::resolve could not be downcast");
-            value.dry_resolve();
-        };
-
-        #[cfg(feature = "ssr")]
-        let resolve = |value: Box<dyn Any>| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::resolve could not be downcast");
-            Box::pin(async move { value.resolve().await.into_any_attr() })
-                as Pin<Box<dyn Future<Output = AnyAttribute> + Send>>
-        };
-        AnyAttribute {
-            type_id: TypeId::of::<T>(),
-            html_len,
-            value,
-            #[cfg(feature = "ssr")]
-            to_html,
-            build,
-            rebuild,
-            #[cfg(feature = "hydrate")]
-            hydrate_from_server,
-            #[cfg(feature = "hydrate")]
-            hydrate_from_template,
-            #[cfg(feature = "ssr")]
-            resolve,
-            #[cfg(feature = "ssr")]
-            dry_resolve,
         }
     }
 }

tachys/src/html/attribute/value.rs

@@ -11,6 +11,26 @@ use std::{
     sync::Arc,
 };
 
+/// Declares that this type can be converted into some other type, which is a valid attribute value.
+pub trait IntoAttributeValue {
+    /// The attribute value into which this type can be converted.
+    type Output;
+
+    /// Consumes this value, transforming it into an attribute value.
+    fn into_attribute_value(self) -> Self::Output;
+}
+
+impl<T> IntoAttributeValue for T
+where
+    T: AttributeValue,
+{
+    type Output = Self;
+
+    fn into_attribute_value(self) -> Self::Output {
+        self
+    }
+}
+
 /// A possible value for an HTML attribute.
 pub trait AttributeValue: Send {
     /// The state that should be retained between building and rebuilding.

tachys/src/html/element/mod.rs

@@ -4,8 +4,8 @@ use crate::{
     renderer::{CastFrom, Rndr},
     ssr::StreamBuilder,
     view::{
-        add_attr::AddAnyAttr, Mountable, Position, PositionState, Render,
-        RenderHtml, ToTemplate,
+        add_attr::AddAnyAttr, IntoRender, Mountable, Position, PositionState,
+        Render, RenderHtml, ToTemplate,
     },
 };
 use const_str_slice_concat::{
@@ -65,11 +65,13 @@ impl<E, At, Ch, NewChild> ElementChild<NewChild> for HtmlElement<E, At, Ch>
 where
     E: ElementWithChildren,
     Ch: Render + NextTuple,
-    <Ch as NextTuple>::Output<NewChild>: Render,
+    <Ch as NextTuple>::Output<NewChild::Output>: Render,
 
-    NewChild: Render,
+    NewChild: IntoRender,
+    NewChild::Output: Render,
 {
-    type Output = HtmlElement<E, At, <Ch as NextTuple>::Output<NewChild>>;
+    type Output =
+        HtmlElement<E, At, <Ch as NextTuple>::Output<NewChild::Output>>;
 
     fn child(self, child: NewChild) -> Self::Output {
         let HtmlElement {
@@ -82,7 +84,7 @@ where
             tag,
 
             attributes,
-            children: children.next_tuple(child),
+            children: children.next_tuple(child.into_render()),
         }
     }
 }
@@ -116,7 +118,7 @@ where
 /// Adds a child to the element.
 pub trait ElementChild<NewChild>
 where
-    NewChild: Render,
+    NewChild: IntoRender,
 {
     /// The type of the element, with the child added.
     type Output;

tachys/src/lib.rs

@@ -19,6 +19,7 @@ pub mod prelude {
                     OnAttribute, OnTargetAttribute, PropAttribute,
                     StyleAttribute,
                 },
+                IntoAttributeValue,
             },
             directive::DirectiveAttribute,
             element::{ElementChild, ElementExt, InnerHtmlAttribute},
@@ -26,8 +27,8 @@ pub mod prelude {
         },
         renderer::{dom::Dom, Renderer},
         view::{
-            add_attr::AddAnyAttr, any_view::IntoAny, Mountable, Render,
-            RenderHtml,
+            add_attr::AddAnyAttr, any_view::IntoAny, IntoRender, Mountable,
+            Render, RenderHtml,
         },
     };
 }

tachys/src/svg/mod.rs

@@ -11,7 +11,7 @@ macro_rules! svg_elements {
 	($($tag:ident  [$($attr:ty),*]),* $(,)?) => {
         paste::paste! {
             $(
-                /// An SVG attribute.
+                /// An SVG element.
                 // `tag()` function
                 #[allow(non_snake_case)]
                 pub fn $tag() -> HtmlElement<[<$tag:camel>], (), ()>
@@ -151,4 +151,33 @@ svg_elements![
   view [],
 ];
 
-// TODO <use>
+/// An SVG element.
+#[allow(non_snake_case)]
+pub fn r#use() -> HtmlElement<Use, (), ()>
+where {
+    HtmlElement {
+        tag: Use,
+        attributes: (),
+        children: (),
+    }
+}
+
+/// An SVG element.
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub struct Use;
+
+impl ElementType for Use {
+    type Output = web_sys::SvgElement;
+
+    const TAG: &'static str = "use";
+    const SELF_CLOSING: bool = false;
+    const ESCAPE_CHILDREN: bool = true;
+    const NAMESPACE: Option<&'static str> = Some("http://www.w3.org/2000/svg");
+
+    #[inline(always)]
+    fn tag(&self) -> &str {
+        Self::TAG
+    }
+}
+
+impl ElementWithChildren for Use {}

tachys/src/view/any_view.rs

@@ -27,7 +27,8 @@ use std::{future::Future, pin::Pin};
 pub struct AnyView {
     type_id: TypeId,
     value: Box<dyn Any + Send>,
-
+    build: fn(Box<dyn Any>) -> AnyViewState,
+    rebuild: fn(TypeId, Box<dyn Any>, &mut AnyViewState),
     // The fields below are cfg-gated so they will not be included in WASM bundles if not needed.
     // Ordinarily, the compiler can simply omit this dead code because the methods are not called.
     // With this type-erased wrapper, however, the compiler is not *always* able to correctly
@@ -42,8 +43,6 @@ pub struct AnyView {
     #[cfg(feature = "ssr")]
     to_html_async_ooo:
         fn(Box<dyn Any>, &mut StreamBuilder, &mut Position, bool, bool),
-    build: fn(Box<dyn Any>) -> AnyViewState,
-    rebuild: fn(TypeId, Box<dyn Any>, &mut AnyViewState),
     #[cfg(feature = "ssr")]
     #[allow(clippy::type_complexity)]
     resolve: fn(Box<dyn Any>) -> Pin<Box<dyn Future<Output = AnyView> + Send>>,
@@ -138,156 +137,172 @@ where
 
         let value = Box::new(self) as Box<dyn Any + Send>;
 
-        #[cfg(feature = "ssr")]
-        let dry_resolve = |value: &mut Box<dyn Any + Send>| {
-            let value = value
-                .downcast_mut::<T>()
-                .expect("AnyView::resolve could not be downcast");
-            value.dry_resolve();
-        };
+        match value.downcast::<AnyView>() {
+            // if it's already an AnyView, we don't need to double-wrap it
+            Ok(any_view) => *any_view,
+            Err(value) => {
+                #[cfg(feature = "ssr")]
+                let dry_resolve = |value: &mut Box<dyn Any + Send>| {
+                    let value = value
+                        .downcast_mut::<T>()
+                        .expect("AnyView::resolve could not be downcast");
+                    value.dry_resolve();
+                };
 
-        #[cfg(feature = "ssr")]
-        let resolve = |value: Box<dyn Any>| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::resolve could not be downcast");
-            Box::pin(async move { value.resolve().await.into_any() })
-                as Pin<Box<dyn Future<Output = AnyView> + Send>>
-        };
-        #[cfg(feature = "ssr")]
-        let to_html = |value: Box<dyn Any>,
-                       buf: &mut String,
-                       position: &mut Position,
-                       escape: bool,
-                       mark_branches: bool| {
-            let type_id = mark_branches
-                .then(|| format!("{:?}", TypeId::of::<T>()))
-                .unwrap_or_default();
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::to_html could not be downcast");
-            if mark_branches {
-                buf.open_branch(&type_id);
-            }
-            value.to_html_with_buf(buf, position, escape, mark_branches);
-            if mark_branches {
-                buf.close_branch(&type_id);
-            }
-        };
-        #[cfg(feature = "ssr")]
-        let to_html_async = |value: Box<dyn Any>,
-                             buf: &mut StreamBuilder,
-                             position: &mut Position,
-                             escape: bool,
-                             mark_branches: bool| {
-            let type_id = mark_branches
-                .then(|| format!("{:?}", TypeId::of::<T>()))
-                .unwrap_or_default();
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::to_html could not be downcast");
-            if mark_branches {
-                buf.open_branch(&type_id);
-            }
-            value.to_html_async_with_buf::<false>(
-                buf,
-                position,
-                escape,
-                mark_branches,
-            );
-            if mark_branches {
-                buf.close_branch(&type_id);
-            }
-        };
-        #[cfg(feature = "ssr")]
-        let to_html_async_ooo =
-            |value: Box<dyn Any>,
-             buf: &mut StreamBuilder,
-             position: &mut Position,
-             escape: bool,
-             mark_branches: bool| {
-                let value = value
-                    .downcast::<T>()
-                    .expect("AnyView::to_html could not be downcast");
-                value.to_html_async_with_buf::<true>(
-                    buf,
-                    position,
-                    escape,
-                    mark_branches,
-                );
-            };
-        let build = |value: Box<dyn Any>| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::build couldn't downcast");
-            let state = Box::new(value.build());
+                #[cfg(feature = "ssr")]
+                let resolve = |value: Box<dyn Any>| {
+                    let value = value
+                        .downcast::<T>()
+                        .expect("AnyView::resolve could not be downcast");
+                    Box::pin(async move { value.resolve().await.into_any() })
+                        as Pin<Box<dyn Future<Output = AnyView> + Send>>
+                };
+                #[cfg(feature = "ssr")]
+                let to_html =
+                    |value: Box<dyn Any>,
+                     buf: &mut String,
+                     position: &mut Position,
+                     escape: bool,
+                     mark_branches: bool| {
+                        let type_id = mark_branches
+                            .then(|| format!("{:?}", TypeId::of::<T>()))
+                            .unwrap_or_default();
+                        let value = value
+                            .downcast::<T>()
+                            .expect("AnyView::to_html could not be downcast");
+                        if mark_branches {
+                            buf.open_branch(&type_id);
+                        }
+                        value.to_html_with_buf(
+                            buf,
+                            position,
+                            escape,
+                            mark_branches,
+                        );
+                        if mark_branches {
+                            buf.close_branch(&type_id);
+                        }
+                    };
+                #[cfg(feature = "ssr")]
+                let to_html_async =
+                    |value: Box<dyn Any>,
+                     buf: &mut StreamBuilder,
+                     position: &mut Position,
+                     escape: bool,
+                     mark_branches: bool| {
+                        let type_id = mark_branches
+                            .then(|| format!("{:?}", TypeId::of::<T>()))
+                            .unwrap_or_default();
+                        let value = value
+                            .downcast::<T>()
+                            .expect("AnyView::to_html could not be downcast");
+                        if mark_branches {
+                            buf.open_branch(&type_id);
+                        }
+                        value.to_html_async_with_buf::<false>(
+                            buf,
+                            position,
+                            escape,
+                            mark_branches,
+                        );
+                        if mark_branches {
+                            buf.close_branch(&type_id);
+                        }
+                    };
+                #[cfg(feature = "ssr")]
+                let to_html_async_ooo =
+                    |value: Box<dyn Any>,
+                     buf: &mut StreamBuilder,
+                     position: &mut Position,
+                     escape: bool,
+                     mark_branches: bool| {
+                        let value = value
+                            .downcast::<T>()
+                            .expect("AnyView::to_html could not be downcast");
+                        value.to_html_async_with_buf::<true>(
+                            buf,
+                            position,
+                            escape,
+                            mark_branches,
+                        );
+                    };
+                let build = |value: Box<dyn Any>| {
+                    let value = value
+                        .downcast::<T>()
+                        .expect("AnyView::build couldn't downcast");
+                    let state = Box::new(value.build());
 
-            AnyViewState {
-                type_id: TypeId::of::<T>(),
-                state,
+                    AnyViewState {
+                        type_id: TypeId::of::<T>(),
+                        state,
 
-                mount: mount_any::<T>,
-                unmount: unmount_any::<T>,
-                insert_before_this: insert_before_this::<T>,
-            }
-        };
-        #[cfg(feature = "hydrate")]
-        let hydrate_from_server =
-            |value: Box<dyn Any>, cursor: &Cursor, position: &PositionState| {
-                let value = value
-                    .downcast::<T>()
-                    .expect("AnyView::hydrate_from_server couldn't downcast");
-                let state = Box::new(value.hydrate::<true>(cursor, position));
+                        mount: mount_any::<T>,
+                        unmount: unmount_any::<T>,
+                        insert_before_this: insert_before_this::<T>,
+                    }
+                };
+                #[cfg(feature = "hydrate")]
+                let hydrate_from_server =
+                    |value: Box<dyn Any>,
+                     cursor: &Cursor,
+                     position: &PositionState| {
+                        let value = value.downcast::<T>().expect(
+                            "AnyView::hydrate_from_server couldn't downcast",
+                        );
+                        let state =
+                            Box::new(value.hydrate::<true>(cursor, position));
 
-                AnyViewState {
+                        AnyViewState {
+                            type_id: TypeId::of::<T>(),
+                            state,
+
+                            mount: mount_any::<T>,
+                            unmount: unmount_any::<T>,
+                            insert_before_this: insert_before_this::<T>,
+                        }
+                    };
+
+                let rebuild =
+                    |new_type_id: TypeId,
+                     value: Box<dyn Any>,
+                     state: &mut AnyViewState| {
+                        let value = value
+                            .downcast::<T>()
+                            .expect("AnyView::rebuild couldn't downcast value");
+                        if new_type_id == state.type_id {
+                            let state = state.state.downcast_mut().expect(
+                                "AnyView::rebuild couldn't downcast state",
+                            );
+                            value.rebuild(state);
+                        } else {
+                            let mut new = value.into_any().build();
+                            state.insert_before_this(&mut new);
+                            state.unmount();
+                            *state = new;
+                        }
+                    };
+
+                AnyView {
                     type_id: TypeId::of::<T>(),
-                    state,
-
-                    mount: mount_any::<T>,
-                    unmount: unmount_any::<T>,
-                    insert_before_this: insert_before_this::<T>,
+                    value,
+                    build,
+                    rebuild,
+                    #[cfg(feature = "ssr")]
+                    resolve,
+                    #[cfg(feature = "ssr")]
+                    dry_resolve,
+                    #[cfg(feature = "ssr")]
+                    html_len,
+                    #[cfg(feature = "ssr")]
+                    to_html,
+                    #[cfg(feature = "ssr")]
+                    to_html_async,
+                    #[cfg(feature = "ssr")]
+                    to_html_async_ooo,
+                    #[cfg(feature = "hydrate")]
+                    hydrate_from_server,
                 }
-            };
-
-        let rebuild = |new_type_id: TypeId,
-                       value: Box<dyn Any>,
-                       state: &mut AnyViewState| {
-            let value = value
-                .downcast::<T>()
-                .expect("AnyView::rebuild couldn't downcast value");
-            if new_type_id == state.type_id {
-                let state = state
-                    .state
-                    .downcast_mut()
-                    .expect("AnyView::rebuild couldn't downcast state");
-                value.rebuild(state);
-            } else {
-                let mut new = value.into_any().build();
-                state.insert_before_this(&mut new);
-                state.unmount();
-                *state = new;
             }
-        };
-
-        AnyView {
-            type_id: TypeId::of::<T>(),
-            value,
-            build,
-            rebuild,
-            #[cfg(feature = "ssr")]
-            resolve,
-            #[cfg(feature = "ssr")]
-            dry_resolve,
-            #[cfg(feature = "ssr")]
-            html_len,
-            #[cfg(feature = "ssr")]
-            to_html,
-            #[cfg(feature = "ssr")]
-            to_html_async,
-            #[cfg(feature = "ssr")]
-            to_html_async_ooo,
-            #[cfg(feature = "hydrate")]
-            hydrate_from_server,
         }
     }
 }
@@ -314,7 +329,7 @@ impl AddAnyAttr for AnyView {
     where
         Self::Output<NewAttr>: RenderHtml,
     {
-        todo!()
+        self
     }
 }
 

tachys/src/view/mod.rs

@@ -432,3 +432,23 @@ pub enum Position {
     /// This is the last child of its parent.
     LastChild,
 }
+
+/// Declares that this type can be converted into some other type, which can be renderered.
+pub trait IntoRender {
+    /// The renderable type into which this type can be converted.
+    type Output;
+
+    /// Consumes this value, transforming it into the renderable type.
+    fn into_render(self) -> Self::Output;
+}
+
+impl<T> IntoRender for T
+where
+    T: Render,
+{
+    type Output = Self;
+
+    fn into_render(self) -> Self::Output {
+        self
+    }
+}