Use local observers

* Check uniqueness of server function names at registration time, and stop leaking src file path in release mode

* Fix missing dev-dependency

README.md

@@ -80,7 +80,7 @@ If you’re on `stable`, note the following:
 
 1. You need to enable the `"stable"` flag in `Cargo.toml`: `leptos = { version = "0.1.0-alpha", features = ["stable"] }`
 2. `nightly` enables the function call syntax for accessing and setting signals. If you’re using `stable`,
-   you’ll just call `.get()`, `.set()`, or `.update()` manually. Check out the 
+   you’ll just call `.get()`, `.set()`, or `.update()` manually. Check out the
    [`counters_stable` example](https://github.com/leptos-rs/leptos/blob/main/examples/counters_stable/src/main.rs)
    for examples of the correct API.
 
@@ -99,6 +99,24 @@ Open browser on [http://localhost:3000/](http://localhost:3000/)
 
 ## FAQs
 
+### Is it production ready?
+
+People usually mean one of three things by this question.
+
+1. **Are the APIs stable?** i.e., will I have to rewrite my whole app from Leptos 0.1 to 0.2 to 0.3 to 0.4, or can I write it now and benefit from new features and updates as new versions come?
+
+With 0.1 the APIs are basically settled. We’re adding new features, but we’re very happy with where the type system and patterns have landed. I would not expect major breaking changes to your code to adapt to, for example, a 0.2.0 release.
+
+2. **Are there bugs?**
+
+Yes, I’m sure there are. You can see from the state of our issue tracker over time that there aren’t that _many_ bugs and they’re usually resolved pretty quickly. But for sure, there may be moments where you encounter something that requires a fix at the framework level, which may not be immediately resolved.
+
+3. **Am I a consumer or a contributor?**
+
+This may be the big one: “production ready” implies a certain orientation to a library: that you can basically use it, without any special knowledge of its internals or ability to contribute. Everyone has this at some level in their stack: for example I (@gbj) don’t have the capacity or knowledge to contribute to something like `wasm-bindgen` at this point: I simply rely on it to work.
+
+There are several people in this community using Leptos right now for internal apps at work, who have also become significant contributors. I think this is the right level of production use for now. There may be missing features that you need, and you may end up building them! But for internal apps, if you’re willing to build and contribute missing pieces along the way, the framework is definitely usable right now.
+
 ### Can I use this for native GUI?
 
 Sure! Obviously the `view` macro is for generating DOM nodes but you can use the reactive system to drive native any GUI toolkit that uses the same kind of object-oriented, event-callback-based framework as the DOM pretty easily. The principles are the same:

examples/counter/README.md

@@ -3,3 +3,5 @@
 This example creates a simple counter in a client side rendered app with Rust and WASM!
 
 To run it, just issue the `trunk serve --open` command in the example root. This will build the app, run it, and open a new browser to serve it.
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/counters/README.md

@@ -0,0 +1,9 @@
+# Leptos Counters Example
+
+This example showcases a basic leptos app with many counters. It is a good example of how to setup a basic reactive app with signals and effects, and how to interact with browser events.
+
+## Client Side Rendering
+
+To run it as a client-side app, you can issue `trunk serve --open` in the root. This will build the entire app into one CSR bundle.
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/counters_stable/README.md

@@ -0,0 +1,9 @@
+# Leptos Counters Example on Rust Stable
+
+This example showcases a basic Leptos app with many counters. It is a good example of how to setup a basic reactive app with signals and effects, and how to interact with browser events. Unlike the other counters example, it will compile on Rust stable, because it has the `stable` feature enabled.
+
+## Client Side Rendering
+
+To run it as a client-side app, you can issue `trunk serve --open` in the root. This will build the entire app into one CSR bundle.
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/fetch/README.md

@@ -0,0 +1,9 @@
+# Client Side Fetch
+
+This example shows how to fetch data from the client in WebAssembly.
+
+## Client Side Rendering
+
+To run it as a client-side app, you can issue `trunk serve --open` in the root. This will build the entire app into one CSR bundle.
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/parent_child/README.md

@@ -0,0 +1,17 @@
+# Parent Child Example
+
+This example highlights four different ways that child components can communicate with their parent:
+
+1. <ButtonA/>: passing a WriteSignal as one of the child component props,
+   for the child component to write into and the parent to read
+2. <ButtonB/>: passing a closure as one of the child component props, for
+   the child component to call
+3. <ButtonC/>: adding a simple event listener on the child component itself
+4. <ButtonD/>: providing a context that is used in the component (rather than prop drilling)
+
+## Client Side Rendering
+
+To run it as a Client Side App, you can issue `trunk serve --open` in the root. This will build the entire
+app into one CSR bundle
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/router/README.md

@@ -1,8 +1,11 @@
 # Leptos Router Example
 
-This example demonstrates how Leptos' router works
+This example demonstrates how Leptos’s router works for client side routing.
+
+## Build and Run it
 
-## Run it
 ```bash
 trunk serve --open
 ```
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

examples/todomvc/README.md

@@ -0,0 +1,10 @@
+# Leptos TodoMVC
+
+This is a Leptos implementation of the TodoMVC example common to many frameworks. This is a relatively-simple application but shows off features like interaction between components and state management.
+
+## Client Side Rendering
+
+To run it as a Client Side App, you can issue `trunk serve --open` in the root. This will build the entire
+app into one CSR bundle.
+
+> If you don't have `trunk` installed, [click here for install instructions.](https://trunkrs.dev/)

integrations/actix/src/lib.rs

@@ -1,5 +1,11 @@
 #![forbid(unsafe_code)]
 
+//! Provides functions to easily integrate Leptos with Actix.
+//!
+//! For more details on how to use the integrations, see the
+//! [`examples`](https://github.com/leptos-rs/leptos/tree/main/examples)
+//! directory in the Leptos repository.
+
 use actix_web::{
     body::BoxBody,
     dev::{ServiceFactory, ServiceRequest},
@@ -68,8 +74,8 @@ impl ResponseOptions {
 }
 
 /// Provides an easy way to redirect the user from within a server function. Mimicing the Remix `redirect()`,
-/// it sets a StatusCode of 302 and a LOCATION header with the provided value.
-/// If looking to redirect from the client, `leptos_router::use_navigate()` should be used instead
+/// it sets a [StatusCode] of 302 and a [LOCATION](header::LOCATION) header with the provided value.
+/// If looking to redirect from the client, `leptos_router::use_navigate()` should be used instead.
 pub async fn redirect(cx: leptos::Scope, path: &str) {
     let response_options = use_context::<ResponseOptions>(cx).unwrap();
     response_options.set_status(StatusCode::FOUND).await;
@@ -114,6 +120,11 @@ pub async fn redirect(cx: leptos::Scope, path: &str) {
 /// }
 /// # }
 /// ```
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [ResponseOptions]
+/// - [HttpRequest](actix_web::HttpRequest)
 pub fn handle_server_fns() -> Route {
     handle_server_fns_with_context(|_cx| {})
 }
@@ -127,7 +138,12 @@ pub fn handle_server_fns() -> Route {
 /// This can then be set up at an appropriate route in your application:
 ///
 /// This version allows you to pass in a closure that adds additional route data to the
-/// context, allowing you to pass in info about the route or user from Actix, or other info
+/// context, allowing you to pass in info about the route or user from Actix, or other info.
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [ResponseOptions]
+/// - [HttpRequest](actix_web::HttpRequest)
 pub fn handle_server_fns_with_context(
     additional_context: impl Fn(leptos::Scope) + 'static + Clone + Send,
 ) -> Route {
@@ -270,6 +286,13 @@ pub fn handle_server_fns_with_context(
 /// }
 /// # }
 /// ```
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [ResponseOptions]
+/// - [HttpRequest](actix_web::HttpRequest)
+/// - [MetaContext](leptos_meta::MetaContext)
+/// - [RouterIntegrationContext](leptos_router::RouterIntegrationContext)
 pub fn render_app_to_stream<IV>(
     options: LeptosOptions,
     app_fn: impl Fn(leptos::Scope) -> IV + Clone + 'static,
@@ -285,6 +308,13 @@ where
 ///
 /// This function allows you to provide additional information to Leptos for your route.
 /// It could be used to pass in Path Info, Connection Info, or anything your heart desires.
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [ResponseOptions]
+/// - [HttpRequest](actix_web::HttpRequest)
+/// - [MetaContext](leptos_meta::MetaContext)
+/// - [RouterIntegrationContext](leptos_router::RouterIntegrationContext)
 pub fn render_app_to_stream_with_context<IV>(
     options: LeptosOptions,
     additional_context: impl Fn(leptos::Scope) + 'static + Clone + Send,
@@ -360,6 +390,13 @@ where
 /// }
 /// # }
 /// ```
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [ResponseOptions]
+/// - [HttpRequest](actix_web::HttpRequest)
+/// - [MetaContext](leptos_meta::MetaContext)
+/// - [RouterIntegrationContext](leptos_router::RouterIntegrationContext)
 pub fn render_preloaded_data_app<Data, Fut, IV>(
     options: LeptosOptions,
     data_fn: impl Fn(HttpRequest) -> Fut + Clone + 'static,

integrations/axum/src/lib.rs

@@ -1,5 +1,11 @@
 #![forbid(unsafe_code)]
 
+//! Provides functions to easily integrate Leptos with Axum.
+//!
+//! For more details on how to use the integrations, see the
+//! [`examples`](https://github.com/leptos-rs/leptos/tree/main/examples)
+//! directory in the Leptos repository.
+
 use axum::{
     body::{Body, Bytes, Full, StreamBody},
     extract::Path,
@@ -91,6 +97,8 @@ pub async fn redirect(cx: leptos::Scope, path: &str) {
         .await;
 }
 
+/// Decomposes an HTTP request into its parts, allowing you to read its headers
+/// and other data without consuming the body.
 pub async fn generate_request_parts(req: Request<Body>) -> RequestParts {
     // provide request headers as context in server scope
     let (parts, body) = req.into_parts();
@@ -107,8 +115,6 @@ pub async fn generate_request_parts(req: Request<Body>) -> RequestParts {
 /// An Axum handlers to listens for a request with Leptos server function arguments in the body,
 /// run the server function if found, and return the resulting [Response].
 ///
-/// This provides an `Arc<[Request<Body>](axum::http::Request)>` [Scope](leptos::Scope).
-///
 /// This can then be set up at an appropriate route in your application:
 ///
 /// ```
@@ -136,6 +142,11 @@ pub async fn generate_request_parts(req: Request<Body>) -> RequestParts {
 /// ```
 /// Leptos provides a generic implementation of `handle_server_fns`. If access to more specific parts of the Request is desired,
 /// you can specify your own server fn handler based on this one and give it it's own route in the server macro.
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [RequestParts]
+/// - [ResponseOptions]
 pub async fn handle_server_fns(
     Path(fn_name): Path<String>,
     headers: HeaderMap,
@@ -147,14 +158,17 @@ pub async fn handle_server_fns(
 /// An Axum handlers to listens for a request with Leptos server function arguments in the body,
 /// run the server function if found, and return the resulting [Response].
 ///
-/// This provides an `Arc<[Request<Body>](axum::http::Request)>` [Scope](leptos::Scope).
-///
 /// This can then be set up at an appropriate route in your application:
 ///
 /// This version allows you to pass in a closure to capture additional data from the layers above leptos
 /// and store it in context. To use it, you'll need to define your own route, and a handler function
-/// that takes in the data you'd like. See the `render_app_to_stream_with_context()` docs for an example
-/// of one that should work much like this one
+/// that takes in the data you'd like. See the [render_app_to_stream_with_context] docs for an example
+/// of one that should work much like this one.
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [RequestParts]
+/// - [ResponseOptions]
 pub async fn handle_server_fns_with_context(
     Path(fn_name): Path<String>,
     headers: HeaderMap,
@@ -330,6 +344,12 @@ pub type PinnedHtmlStream = Pin<Box<dyn Stream<Item = io::Result<Bytes>> + Send>
 /// # }
 /// ```
 ///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [RequestParts]
+/// - [ResponseOptions]
+/// - [MetaContext](leptos_meta::MetaContext)
+/// - [RouterIntegrationContext](leptos_router::RouterIntegrationContext)
 pub fn render_app_to_stream<IV>(
     options: LeptosOptions,
     app_fn: impl Fn(leptos::Scope) -> IV + Clone + Send + 'static,
@@ -362,8 +382,14 @@ where
 ///     handler(req).await.into_response()
 /// }
 /// ```
-/// Otherwise, this function is identical to the `render_app_with_stream() function, which has more info about how this works.`
-
+/// Otherwise, this function is identical to [render_app_to_stream].
+///
+/// ## Provided Context Types
+/// This function always provides context values including the following types:
+/// - [RequestParts]
+/// - [ResponseOptions]
+/// - [MetaContext](leptos_meta::MetaContext)
+/// - [RouterIntegrationContext](leptos_router::RouterIntegrationContext)
 pub fn render_app_to_stream_with_context<IV>(
     options: LeptosOptions,
     additional_context: impl Fn(leptos::Scope) + 'static + Clone + Send,

leptos/src/lib.rs

@@ -8,9 +8,8 @@
 //!   or mutating data via async requests to the server
 //! - multi-page apps (MPAs) rendered on the server, managing navigation, data, and mutations via
 //!   web-standard `<a>` and `<form>` tags
-//! - progressively-enhanced multi-page apps ([PEMPAs](https://www.epicweb.dev/the-webs-next-transition)?)
-//!   that are rendered on the server and then hydrated on the client, enhancing your `<a>` and `<form>`
-//!   navigations and mutations seamlessly when WASM is available.
+//! - progressively-enhanced single-page apps that are rendered on the server and then hydrated on the client,
+//!   enhancing your `<a>` and `<form>` navigations and mutations seamlessly when WASM is available.
 //!
 //! And you can do all three of these **using the same Leptos code.**
 //!
@@ -24,12 +23,17 @@
 //!
 //! # Learning by Example
 //!
-//! These docs are a work in progress. If you want to see what Leptos is capable of, check out
+//! If you want to see what Leptos is capable of, check out
 //! the [examples](https://github.com/leptos-rs/leptos/tree/main/examples):
 //! - [`counter`](https://github.com/leptos-rs/leptos/tree/main/examples/counter) is the classic
 //!   counter example, showing the basics of client-side rendering and reactive DOM updates
+//! - [`counter_without_macros`](https://github.com/leptos-rs/leptos/tree/main/examples/counter_without_macros)
+//!   adapts the counter example to use the builder pattern for the UI and avoids other macros, instead showing
+//!   the code that Leptos generates.
 //! - [`counters`](https://github.com/leptos-rs/leptos/tree/main/examples/counters) introduces parent-child
 //!   communication via contexts, and the `<For/>` component for efficient keyed list updates.
+//! - [`counters_stable`](https://github.com/leptos-rs/leptos/tree/main/examples/counters_stable) adapts the `counters` example
+//!   to show how to use Leptos with `stable` Rust.
 //! - [`parent_child`](https://github.com/leptos-rs/leptos/tree/main/examples/parent_child) shows four different
 //!   ways a parent component can communicate with a child, including passing a closure, context, and more
 //! - [`todomvc`](https://github.com/leptos-rs/leptos/tree/main/examples/todomvc) implements the classic to-do
@@ -42,15 +46,23 @@
 //!   HTTP request within your reactive code.
 //! - [`router`](https://github.com/leptos-rs/leptos/tree/main/examples/router) shows how to use Leptos’s nested router
 //!   to enable client-side navigation and route-specific, reactive data loading.
+//! - [`counter_isomorphic`](https://github.com/leptos-rs/leptos/tree/main/examples/counter_isomorphic) shows
+//!   different methods of interaction with a stateful server, including server functions, server actions, forms,
+//!   and server-sent events (SSE).
 //! - [`todomvc`](https://github.com/leptos-rs/leptos/tree/main/examples/todomvc) shows the basics of building an
 //!   isomorphic web app. Both the server and the client import the same app code from the `todomvc` example.
 //!   The server renders the app directly to an HTML string, and the client hydrates that HTML to make it interactive.
-//! - [`hackernews`](https://github.com/leptos-rs/leptos/tree/main/examples/hackernews) pulls everything together.
-//!   It integrates calls to a real external REST API, routing, server-side rendering and hydration to create
-//!   a fully-functional PEMPA that works as intended even before WASM has loaded and begun to run.
+//! - [`hackernews`](https://github.com/leptos-rs/leptos/tree/main/examples/hackernews)
+//!   and [`hackernews_axum`](https://github.com/leptos-rs/leptos/tree/main/examples/hackernews_axum)
+//!   integrate calls to a real external REST API, routing, server-side rendering and hydration to create
+//!   a fully-functional that works as intended even before WASM has loaded and begun to run.
+//! - [`todo_app_sqlite`](https://github.com/leptos-rs/leptos/tree/main/examples/todo_app_sqlite) and
+//!   [`todo_app_sqlite_axum`](https://github.com/leptos-rs/leptos/tree/main/examples/todo_app_sqlite_axum)
+//!   show how to build a full-stack app using server functions and database connections.
+//! - [`tailwind`](https://github.com/leptos-rs/leptos/tree/main/examples/tailwind) shows how to integrate
+//!   TailwindCSS with `cargo-leptos`.
 //!
-//! (The SPA examples can be run using `trunk serve`. For information about Trunk,
-//! [see here]((https://trunkrs.dev/)).)
+//! Details on how to run each example can be found in its README.
 //!
 //! # Quick Links
 //!

leptos_config/src/lib.rs

@@ -72,8 +72,8 @@ fn env_w_default(key: &str, default: &str) -> Result<String, LeptosConfigError>
     }
 }
 
-/// An enum that can be used to define the environment Leptos is running in. Can be passed to [RenderOptions].
-/// Setting this to the `PROD` variant will not include the websockets code for `cargo-leptos` watch mode.
+/// An enum that can be used to define the environment Leptos is running in.
+/// Setting this to the `PROD` variant will not include the WebSocket code for `cargo-leptos` watch mode.
 /// Defaults to `DEV`.
 #[derive(Debug, Clone, serde::Deserialize)]
 pub enum Env {

leptos_dom/src/components.rs

@@ -28,12 +28,12 @@ use wasm_bindgen::JsCast;
 #[derive(educe::Educe)]
 #[educe(Default, Clone, PartialEq, Eq)]
 pub enum CoreComponent {
-  /// The [`Unit`] component.
+  /// The [Unit] component.
   #[educe(Default)]
   Unit(UnitRepr),
-  /// The [`DynChild`] component.
+  /// The [DynChild] component.
   DynChild(DynChildRepr),
-  /// The [`EachKey`] component.
+  /// The [Each] component.
   Each(EachRepr),
 }
 

leptos_dom/src/lib.rs

@@ -31,7 +31,7 @@ pub use hydration::{HydrationCtx, HydrationKey};
 pub use js_sys;
 use leptos_reactive::Scope;
 pub use logging::*;
-pub use macro_helpers::{IntoAttribute, IntoClass, IntoProperty};
+pub use macro_helpers::*;
 pub use node_ref::*;
 #[cfg(all(target_arch = "wasm32", feature = "web"))]
 use once_cell::unsync::Lazy as LazyCell;

leptos_dom/src/ssr.rs

@@ -78,7 +78,7 @@ pub fn render_to_stream_with_prefix(
   stream
 }
 
-/// Renders a function to a stream of HTML strings and returns the [Scope] and [Runtime] that were created, so
+/// Renders a function to a stream of HTML strings and returns the [Scope] and [RuntimeId] that were created, so
 /// they can be disposed when appropriate. After the `view` runs, the `prefix` will run with
 /// the same scope. This can be used to generate additional HTML that has access to the same `Scope`.
 ///
@@ -100,7 +100,7 @@ pub fn render_to_stream_with_prefix_undisposed(
   render_to_stream_with_prefix_undisposed_with_context(view, prefix, |_cx| {})
 }
 
-/// Renders a function to a stream of HTML strings and returns the [Scope] and [Runtime] that were created, so
+/// Renders a function to a stream of HTML strings and returns the [Scope] and [RuntimeId] that were created, so
 /// they can be disposed when appropriate. After the `view` runs, the `prefix` will run with
 /// the same scope. This can be used to generate additional HTML that has access to the same `Scope`.
 ///

leptos_macro/src/lib.rs

@@ -198,7 +198,7 @@ mod server;
 /// ```
 ///
 /// 8. You can use the `node_ref` or `_ref` attribute to store a reference to its DOM element in a
-///    [NodeRef](leptos_reactive::NodeRef) to use later.
+///    [NodeRef](leptos_dom::NodeRef) to use later.
 /// ```rust
 /// # use leptos::*;
 /// # run_scope(create_runtime(), |cx| {
@@ -315,10 +315,10 @@ pub fn view(tokens: TokenStream) -> TokenStream {
 /// Annotates a function so that it can be used with your template as a Leptos `<Component/>`.
 ///
 /// The `#[component]` macro allows you to annotate plain Rust functions as components
-/// and use them within your Leptos [view](mod@view) as if they were custom HTML elements. The
+/// and use them within your Leptos [view](crate::view!) as if they were custom HTML elements. The
 /// component function takes a [Scope](leptos_reactive::Scope) and any number of other arguments.
 /// When you use the component somewhere else, the names of its arguments are the names
-/// of the properties you use in the [view](mod@view) macro.
+/// of the properties you use in the [view](crate::view!) macro.
 ///
 /// Every component function should have the return type `-> impl IntoView`.
 ///
@@ -554,11 +554,11 @@ pub fn component(args: proc_macro::TokenStream, s: TokenStream) -> TokenStream {
 ///   (e.g., `"/api"`). Defaults to `"/"`.
 /// 3. *Optional*: either `"Cbor"` (specifying that it should use the binary `cbor` format for
 ///   serialization) or `"Url"` (specifying that it should be use a URL-encoded form-data string).
-///   Defaults to `"Url"`. If you want to use this server function to power an
-///   [ActionForm](leptos_router::ActionForm) the encoding must be `"Url"`.
+///   Defaults to `"Url"`. If you want to use this server function to power a `<form>` that will
+///   work without WebAssembly, the encoding must be `"Url"`.
 ///
 /// The server function itself can take any number of arguments, each of which should be serializable
-/// and deserializable with `serde`. Optionally, its first argument can be a Leptos [Scope](leptos::Scope),
+/// and deserializable with `serde`. Optionally, its first argument can be a Leptos [Scope](leptos_reactive::Scope),
 /// which will be injected *on the server side.* This can be used to inject the raw HTTP request or other
 /// server-side context into the server function.
 ///

leptos_macro/src/server.rs

@@ -43,7 +43,7 @@ pub fn server_macro_impl(args: proc_macro::TokenStream, s: TokenStream2) -> Resu
     let block = body.block;
 
     cfg_if! {
-        if #[cfg(not(feature = "stable"))] {
+        if #[cfg(all(not(feature = "stable"), debug_assertions))] {
             use proc_macro::Span;
             let span = Span::call_site();
             #[cfg(not(target_os = "windows"))]
@@ -71,6 +71,7 @@ pub fn server_macro_impl(args: proc_macro::TokenStream, s: TokenStream2) -> Resu
     let cx_assign_statement = if let Some(FnArg::Typed(arg)) = cx_arg {
         if let Pat::Ident(id) = &*arg.pat {
             quote! {
+                #[allow(unused)]
                 let #id = cx;
             }
         } else {
@@ -90,7 +91,15 @@ pub fn server_macro_impl(args: proc_macro::TokenStream, s: TokenStream2) -> Resu
             FnArg::Receiver(_) => panic!("cannot use receiver types in server function macro"),
             FnArg::Typed(t) => t,
         };
-        quote! { #typed_arg }
+        let is_cx = fn_arg_is_cx(f);
+        if is_cx {
+            quote! {
+                #[allow(unused)]
+                #typed_arg
+            }
+        } else {
+            quote! { #typed_arg }
+        }
     });
     let fn_args_2 = fn_args.clone();
 

leptos_reactive/Cargo.toml

@@ -8,16 +8,16 @@ repository = "https://github.com/leptos-rs/leptos"
 description = "Reactive system for the Leptos web framework."
 
 [dependencies]
-log = "0.4"
 slotmap = { version = "1", features = ["serde"] }
 serde = { version = "1", features = ["derive"] }
 serde-lite = { version = "0.3", optional = true }
 futures = { version = "0.3" }
 js-sys = "0.3"
+lazy_static = "1"
 miniserde = { version = "0.1", optional = true }
+parking_lot = "0.12"
 serde-wasm-bindgen = "0.4"
 serde_json = "1"
-base64 = "0.21"
 thiserror = "1"
 tokio = { version = "1", features = ["rt"], optional = true }
 tracing = "0.1"

leptos_reactive/src/context.rs

@@ -57,7 +57,7 @@ where
     let id = value.type_id();
 
     _ = with_runtime(cx.runtime, |runtime| {
-        let mut contexts = runtime.scope_contexts.borrow_mut();
+        let mut contexts = runtime.scope_contexts.write();
         let context = contexts.entry(cx.id).unwrap().or_insert_with(HashMap::new);
         context.insert(id, Box::new(value) as Box<dyn Any>);
     });
@@ -116,7 +116,7 @@ where
     let id = TypeId::of::<T>();
     with_runtime(cx.runtime, |runtime| {
         let local_value = {
-            let contexts = runtime.scope_contexts.borrow();
+            let contexts = runtime.scope_contexts.read();
             let context = contexts.get(cx.id);
             context
                 .and_then(|context| context.get(&id).and_then(|val| val.downcast_ref::<T>()))
@@ -124,16 +124,12 @@ where
         };
         match local_value {
             Some(val) => Some(val),
-            None => runtime
-                .scope_parents
-                .borrow()
-                .get(cx.id)
-                .and_then(|parent| {
-                    use_context::<T>(Scope {
-                        runtime: cx.runtime,
-                        id: *parent,
-                    })
-                }),
+            None => runtime.scope_parents.read().get(cx.id).and_then(|parent| {
+                use_context::<T>(Scope {
+                    runtime: cx.runtime,
+                    id: *parent,
+                })
+            }),
         }
     })
     .ok()

leptos_reactive/src/effect.rs

@@ -1,8 +1,8 @@
 #![forbid(unsafe_code)]
-use crate::runtime::{with_runtime, RuntimeId};
+use crate::runtime::{with_runtime, LocalObserver, RuntimeId};
 use crate::{debug_warn, Runtime, Scope, ScopeProperty};
 use cfg_if::cfg_if;
-use std::cell::RefCell;
+use parking_lot::RwLock;
 use std::fmt::Debug;
 
 /// Effects run a certain chunk of code whenever the signals they depend on change.
@@ -23,7 +23,6 @@ use std::fmt::Debug;
 /// the server, use [create_isomorphic_effect].
 /// ```
 /// # use leptos_reactive::*;
-/// # use log::*;
 /// # create_scope(create_runtime(), |cx| {
 /// let (a, set_a) = create_signal(cx, 0);
 /// let (b, set_b) = create_signal(cx, 0);
@@ -31,7 +30,7 @@ use std::fmt::Debug;
 /// // ✅ use effects to interact between reactive state and the outside world
 /// create_effect(cx, move |_| {
 ///   // immediately prints "Value: 0" and subscribes to `a`
-///   log::debug!("Value: {}", a());
+///   println!("Value: {}", a());
 /// });
 ///
 /// set_a(1);
@@ -80,7 +79,6 @@ where
 /// the server as well as the client.
 /// ```
 /// # use leptos_reactive::*;
-/// # use log::*;
 /// # create_scope(create_runtime(), |cx| {
 /// let (a, set_a) = create_signal(cx, 0);
 /// let (b, set_b) = create_signal(cx, 0);
@@ -88,7 +86,7 @@ where
 /// // ✅ use effects to interact between reactive state and the outside world
 /// create_isomorphic_effect(cx, move |_| {
 ///   // immediately prints "Value: 0" and subscribes to `a`
-///   log::debug!("Value: {}", a());
+///   println!("Value: {}", a());
 /// });
 ///
 /// set_a(1);
@@ -152,7 +150,7 @@ where
     F: Fn(Option<T>) -> T,
 {
     pub(crate) f: F,
-    pub(crate) value: RefCell<Option<T>>,
+    pub(crate) value: RwLock<Option<T>>,
     #[cfg(debug_assertions)]
     pub(crate) defined_at: &'static std::panic::Location<'static>,
 }
@@ -179,22 +177,22 @@ where
             )
         )
     )]
-    fn run(&self, id: EffectId, runtime: RuntimeId) {
-        _ = with_runtime(runtime, |runtime| {
+    fn run(&self, id: EffectId, runtime_id: RuntimeId) {
+        _ = with_runtime(runtime_id, |runtime| {
             // clear previous dependencies
             id.cleanup(runtime);
 
             // set this as the current observer
-            let prev_observer = runtime.observer.take();
-            runtime.observer.set(Some(id));
+            let prev_observer = LocalObserver::take(runtime_id);
+            LocalObserver::set(runtime_id, Some(id));
 
             // run the effect
-            let value = self.value.take();
+            let value = std::mem::take(&mut *self.value.write());
             let new_value = (self.f)(value);
-            *self.value.borrow_mut() = Some(new_value);
+            *self.value.write() = Some(new_value);
 
             // restore the previous observer
-            runtime.observer.set(prev_observer);
+            LocalObserver::set(runtime_id, prev_observer);
         })
     }
 }
@@ -203,7 +201,7 @@ impl EffectId {
     pub(crate) fn run<T>(&self, runtime_id: RuntimeId) {
         _ = with_runtime(runtime_id, |runtime| {
             let effect = {
-                let effects = runtime.effects.borrow();
+                let effects = runtime.effects.read();
                 effects.get(*self).cloned()
             };
             if let Some(effect) = effect {
@@ -226,12 +224,12 @@ impl EffectId {
         )
     )]
     pub(crate) fn cleanup(&self, runtime: &Runtime) {
-        let sources = runtime.effect_sources.borrow();
+        let sources = runtime.effect_sources.read();
         if let Some(sources) = sources.get(*self) {
-            let subs = runtime.signal_subscribers.borrow();
-            for source in sources.borrow().iter() {
+            let subs = runtime.signal_subscribers.read();
+            for source in sources.read().iter() {
                 if let Some(source) = subs.get(*source) {
-                    source.borrow_mut().remove(self);
+                    source.write().remove(self);
                 }
             }
         }

leptos_reactive/src/lib.rs

@@ -146,7 +146,7 @@ macro_rules! debug_warn {
         {
             #[cfg(debug_assertions)]
             {
-                log::warn!($($x)*)
+                tracing::warn!($($x)*)
             }
             #[cfg(not(debug_assertions))]
             { }

leptos_reactive/src/memo.rs

@@ -33,7 +33,7 @@ use std::fmt::Debug;
 /// let expensive = move || really_expensive_computation(value()); // lazy: doesn't run until called
 /// create_effect(cx, move |_| {
 ///   // 🆗 run #1: calls `really_expensive_computation` the first time
-///   log::debug!("expensive = {}", expensive());
+///   println!("expensive = {}", expensive());
 /// });
 /// create_effect(cx, move |_| {
 ///   // ❌ run #2: this calls `really_expensive_computation` a second time!
@@ -46,7 +46,7 @@ use std::fmt::Debug;
 /// let memoized = create_memo(cx, move |_| really_expensive_computation(value()));
 /// create_effect(cx, move |_| {
 ///  // 🆗 reads the current value of the memo
-///   log::debug!("memoized = {}", memoized());
+///   println!("memoized = {}", memoized());
 /// });
 /// create_effect(cx, move |_| {
 ///   // ✅ reads the current value **without re-running the calculation**
@@ -103,7 +103,7 @@ where
 /// let expensive = move || really_expensive_computation(value()); // lazy: doesn't run until called
 /// create_effect(cx, move |_| {
 ///   // 🆗 run #1: calls `really_expensive_computation` the first time
-///   log::debug!("expensive = {}", expensive());
+///   println!("expensive = {}", expensive());
 /// });
 /// create_effect(cx, move |_| {
 ///   // ❌ run #2: this calls `really_expensive_computation` a second time!
@@ -116,7 +116,7 @@ where
 /// let memoized = create_memo(cx, move |_| really_expensive_computation(value()));
 /// create_effect(cx, move |_| {
 ///  // 🆗 reads the current value of the memo
-///   log::debug!("memoized = {}", memoized());
+///   println!("memoized = {}", memoized());
 /// });
 /// create_effect(cx, move |_| {
 ///   // ✅ reads the current value **without re-running the calculation**

leptos_reactive/src/resource.rs

@@ -6,15 +6,10 @@ use crate::{
     spawn::spawn_local,
     use_context, Memo, ReadSignal, Scope, ScopeProperty, SuspenseContext, WriteSignal,
 };
+use parking_lot::RwLock;
 use std::{
-    any::Any,
-    cell::{Cell, RefCell},
-    collections::HashSet,
-    fmt::Debug,
-    future::Future,
-    marker::PhantomData,
-    pin::Pin,
-    rc::Rc,
+    any::Any, collections::HashSet, fmt::Debug, future::Future, marker::PhantomData, pin::Pin,
+    sync::Arc,
 };
 
 /// Creates [Resource](crate::Resource), which is a signal that reflects the
@@ -113,10 +108,10 @@ where
 
     let (loading, set_loading) = create_signal(cx, false);
 
-    let fetcher = Rc::new(move |s| Box::pin(fetcher(s)) as Pin<Box<dyn Future<Output = T>>>);
+    let fetcher = Arc::new(move |s| Box::pin(fetcher(s)) as Pin<Box<dyn Future<Output = T>>>);
     let source = create_memo(cx, move |_| source());
 
-    let r = Rc::new(ResourceState {
+    let r = Arc::new(ResourceState {
         scope: cx,
         value,
         set_value,
@@ -124,18 +119,18 @@ where
         set_loading,
         source,
         fetcher,
-        resolved: Rc::new(Cell::new(resolved)),
-        scheduled: Rc::new(Cell::new(false)),
+        resolved: Arc::new(RwLock::new(resolved)),
+        scheduled: Arc::new(RwLock::new(false)),
         suspense_contexts: Default::default(),
     });
 
     let id = with_runtime(cx.runtime, |runtime| {
-        runtime.create_serializable_resource(Rc::clone(&r))
+        runtime.create_serializable_resource(Arc::clone(&r))
     })
     .expect("tried to create a Resource in a Runtime that has been disposed.");
 
     create_isomorphic_effect(cx, {
-        let r = Rc::clone(&r);
+        let r = Arc::clone(&r);
         move |_| {
             load_resource(cx, id, r.clone());
         }
@@ -233,10 +228,10 @@ where
 
     let (loading, set_loading) = create_signal(cx, false);
 
-    let fetcher = Rc::new(move |s| Box::pin(fetcher(s)) as Pin<Box<dyn Future<Output = T>>>);
+    let fetcher = Arc::new(move |s| Box::pin(fetcher(s)) as Pin<Box<dyn Future<Output = T>>>);
     let source = create_memo(cx, move |_| source());
 
-    let r = Rc::new(ResourceState {
+    let r = Arc::new(ResourceState {
         scope: cx,
         value,
         set_value,
@@ -244,18 +239,18 @@ where
         set_loading,
         source,
         fetcher,
-        resolved: Rc::new(Cell::new(resolved)),
-        scheduled: Rc::new(Cell::new(false)),
+        resolved: Arc::new(RwLock::new(resolved)),
+        scheduled: Arc::new(RwLock::new(false)),
         suspense_contexts: Default::default(),
     });
 
     let id = with_runtime(cx.runtime, |runtime| {
-        runtime.create_unserializable_resource(Rc::clone(&r))
+        runtime.create_unserializable_resource(Arc::clone(&r))
     })
     .expect("tried to create a Resource in a runtime that has been disposed.");
 
     create_effect(cx, {
-        let r = Rc::clone(&r);
+        let r = Arc::clone(&r);
         // This is a local resource, so we're always going to handle it on the
         // client
         move |_| r.load(false)
@@ -274,7 +269,7 @@ where
 }
 
 #[cfg(not(feature = "hydrate"))]
-fn load_resource<S, T>(_cx: Scope, _id: ResourceId, r: Rc<ResourceState<S, T>>)
+fn load_resource<S, T>(_cx: Scope, _id: ResourceId, r: Arc<ResourceState<S, T>>)
 where
     S: PartialEq + Debug + Clone + 'static,
     T: 'static,
@@ -283,7 +278,7 @@ where
 }
 
 #[cfg(feature = "hydrate")]
-fn load_resource<S, T>(cx: Scope, id: ResourceId, r: Rc<ResourceState<S, T>>)
+fn load_resource<S, T>(cx: Scope, id: ResourceId, r: Arc<ResourceState<S, T>>)
 where
     S: PartialEq + Debug + Clone + 'static,
     T: Serializable + 'static,
@@ -291,12 +286,12 @@ where
     use wasm_bindgen::{JsCast, UnwrapThrowExt};
 
     _ = with_runtime(cx.runtime, |runtime| {
-        let mut context = runtime.shared_context.borrow_mut();
+        let mut context = runtime.shared_context.write();
         if let Some(data) = context.resolved_resources.remove(&id) {
             // The server already sent us the serialized resource value, so
             // deserialize & set it now
             context.pending_resources.remove(&id); // no longer pending
-            r.resolved.set(true);
+            *r.resolved.write() = true;
 
             let res = T::from_json(&data).expect_throw("could not deserialize Resource JSON");
 
@@ -318,7 +313,7 @@ where
                 move |res: String| {
                     let res =
                         T::from_json(&res).expect_throw("could not deserialize Resource JSON");
-                    resolved.set(true);
+                    *resolved.write() = true;
                     set_value.update(|n| *n = Some(res));
                     set_loading.update(|n| *n = false);
                 }
@@ -551,10 +546,10 @@ where
     set_loading: WriteSignal<bool>,
     source: Memo<S>,
     #[allow(clippy::type_complexity)]
-    fetcher: Rc<dyn Fn(S) -> Pin<Box<dyn Future<Output = T>>>>,
-    resolved: Rc<Cell<bool>>,
-    scheduled: Rc<Cell<bool>>,
-    suspense_contexts: Rc<RefCell<HashSet<SuspenseContext>>>,
+    fetcher: Arc<dyn Fn(S) -> Pin<Box<dyn Future<Output = T>>>>,
+    resolved: Arc<RwLock<bool>>,
+    scheduled: Arc<RwLock<bool>>,
+    suspense_contexts: Arc<RwLock<HashSet<SuspenseContext>>>,
 }
 
 impl<S, T> ResourceState<S, T>
@@ -583,7 +578,7 @@ where
 
         let increment = move |_: Option<()>| {
             if let Some(s) = &suspense_cx {
-                let mut contexts = suspense_contexts.borrow_mut();
+                let mut contexts = suspense_contexts.write();
                 if !contexts.contains(s) {
                     contexts.insert(*s);
 
@@ -607,21 +602,22 @@ where
 
     fn load(&self, refetching: bool) {
         // doesn't refetch if already refetching
-        if refetching && self.scheduled.get() {
+        let mut scheduled = self.scheduled.write();
+        if refetching && *scheduled {
             return;
         }
 
-        self.scheduled.set(false);
+        *scheduled = false;
 
         _ = self.source.try_with(|source| {
             let fut = (self.fetcher)(source.clone());
 
             // `scheduled` is true for the rest of this code only
-            self.scheduled.set(true);
+            *self.scheduled.write() = true;
             queue_microtask({
-                let scheduled = Rc::clone(&self.scheduled);
+                let scheduled = Arc::clone(&self.scheduled);
                 move || {
-                    scheduled.set(false);
+                    *scheduled.write() = false;
                 }
             });
 
@@ -630,7 +626,7 @@ where
             // increment counter everywhere it's read
             let suspense_contexts = self.suspense_contexts.clone();
 
-            for suspense_context in suspense_contexts.borrow().iter() {
+            for suspense_context in suspense_contexts.read().iter() {
                 suspense_context.increment();
             }
 
@@ -642,12 +638,12 @@ where
                 async move {
                     let res = fut.await;
 
-                    resolved.set(true);
+                    *resolved.write() = true;
 
                     set_value.update(|n| *n = Some(res));
                     set_loading.update(|n| *n = false);
 
-                    for suspense_context in suspense_contexts.borrow().iter() {
+                    for suspense_context in suspense_contexts.read().iter() {
                         suspense_context.decrement();
                     }
                 }
@@ -686,8 +682,8 @@ where
 }
 
 pub(crate) enum AnyResource {
-    Unserializable(Rc<dyn UnserializableResource>),
-    Serializable(Rc<dyn SerializableResource>),
+    Unserializable(Arc<dyn UnserializableResource + Send + Sync>),
+    Serializable(Arc<dyn SerializableResource + Send + Sync>),
 }
 
 pub(crate) trait SerializableResource {

leptos_reactive/src/runtime.rs

@@ -6,28 +6,30 @@ use crate::{
 };
 use cfg_if::cfg_if;
 use futures::stream::FuturesUnordered;
+use lazy_static::lazy_static;
+use parking_lot::RwLock;
 use slotmap::{SecondaryMap, SlotMap, SparseSecondaryMap};
 use std::{
     any::{Any, TypeId},
-    cell::{Cell, RefCell},
+    cell::RefCell,
     collections::{HashMap, HashSet},
     fmt::Debug,
     future::Future,
     marker::PhantomData,
     pin::Pin,
-    rc::Rc,
+    sync::Arc,
 };
 
 pub(crate) type PinnedFuture<T> = Pin<Box<dyn Future<Output = T>>>;
 
 cfg_if! {
     if #[cfg(any(feature = "csr", feature = "hydrate"))] {
-        thread_local! {
-            pub(crate) static RUNTIME: Runtime = Runtime::new();
+        lazy_static! {
+            pub(crate) static ref RUNTIME: Runtime = Runtime::new();
         }
     } else {
-        thread_local! {
-            pub(crate) static RUNTIMES: RefCell<SlotMap<RuntimeId, Runtime>> = Default::default();
+        lazy_static! {
+            pub(crate) static ref RUNTIMES: RwLock<SlotMap<RuntimeId, Runtime>> = Default::default();
         }
     }
 }
@@ -39,15 +41,13 @@ pub(crate) fn with_runtime<T>(id: RuntimeId, f: impl FnOnce(&Runtime) -> T) -> R
     cfg_if! {
         if #[cfg(any(feature = "csr", feature = "hydrate"))] {
             _ = id;
-            Ok(RUNTIME.with(|runtime| f(runtime)))
+            Ok(f(&RUNTIME))
         } else {
-            RUNTIMES.with(|runtimes| {
-                let runtimes = runtimes.borrow();
-                match runtimes.get(id) {
-                    None => Err(()),
-                    Some(runtime) => Ok(f(runtime))
-                }
-            })
+            let runtimes = RUNTIMES.read();
+            match runtimes.get(id) {
+                None => Err(()),
+                Some(runtime) => Ok(f(runtime))
+            }
         }
     }
 }
@@ -60,7 +60,7 @@ pub fn create_runtime() -> RuntimeId {
         if #[cfg(any(feature = "csr", feature = "hydrate"))] {
             Default::default()
         } else {
-            RUNTIMES.with(|runtimes| runtimes.borrow_mut().insert(Runtime::new()))
+            RUNTIMES.with(|runtimes| runtimes.write().insert(Runtime::new()))
         }
     }
 }
@@ -75,7 +75,7 @@ impl RuntimeId {
     pub fn dispose(self) {
         cfg_if! {
             if #[cfg(not(any(feature = "csr", feature = "hydrate")))] {
-                let runtime = RUNTIMES.with(move |runtimes| runtimes.borrow_mut().remove(self));
+                let runtime = RUNTIMES.with(move |runtimes| runtimes.write().remove(self));
                 drop(runtime);
             }
         }
@@ -83,7 +83,7 @@ impl RuntimeId {
 
     pub(crate) fn raw_scope_and_disposer(self) -> (Scope, ScopeDisposer) {
         with_runtime(self, |runtime| {
-            let id = { runtime.scopes.borrow_mut().insert(Default::default()) };
+            let id = { runtime.scopes.write().insert(Default::default()) };
             let scope = Scope { runtime: self, id };
             let disposer = ScopeDisposer(Box::new(move || scope.dispose()));
             (scope, disposer)
@@ -97,9 +97,9 @@ impl RuntimeId {
         parent: Option<Scope>,
     ) -> (T, ScopeId, ScopeDisposer) {
         with_runtime(self, |runtime| {
-            let id = { runtime.scopes.borrow_mut().insert(Default::default()) };
+            let id = { runtime.scopes.write().insert(Default::default()) };
             if let Some(parent) = parent {
-                runtime.scope_parents.borrow_mut().insert(id, parent.id);
+                runtime.scope_parents.write().insert(id, parent.id);
             }
             let scope = Scope { runtime: self, id };
             let val = f(scope);
@@ -121,10 +121,7 @@ impl RuntimeId {
         T: Any + 'static,
     {
         let id = with_runtime(self, |runtime| {
-            runtime
-                .signals
-                .borrow_mut()
-                .insert(Rc::new(RefCell::new(value)))
+            runtime.signals.write().insert(Arc::new(RwLock::new(value)))
         })
         .expect("tried to create a signal in a runtime that has been disposed");
         (
@@ -150,10 +147,7 @@ impl RuntimeId {
         T: Any + 'static,
     {
         let id = with_runtime(self, |runtime| {
-            runtime
-                .signals
-                .borrow_mut()
-                .insert(Rc::new(RefCell::new(value)))
+            runtime.signals.write().insert(Arc::new(RwLock::new(value)))
         })
         .expect("tried to create a signal in a runtime that has been disposed");
         RwSignal {
@@ -176,11 +170,11 @@ impl RuntimeId {
         with_runtime(self, |runtime| {
             let effect = Effect {
                 f,
-                value: RefCell::new(None),
+                value: RwLock::new(None),
                 #[cfg(debug_assertions)]
                 defined_at,
             };
-            let id = { runtime.effects.borrow_mut().insert(Rc::new(effect)) };
+            let id = { runtime.effects.write().insert(Arc::new(effect)) };
             id.run::<T>(self);
             id
         })
@@ -219,33 +213,63 @@ impl RuntimeId {
 
 #[derive(Default)]
 pub(crate) struct Runtime {
-    pub shared_context: RefCell<SharedContext>,
-    pub observer: Cell<Option<EffectId>>,
-    pub scopes: RefCell<SlotMap<ScopeId, RefCell<Vec<ScopeProperty>>>>,
-    pub scope_parents: RefCell<SparseSecondaryMap<ScopeId, ScopeId>>,
-    pub scope_children: RefCell<SparseSecondaryMap<ScopeId, Vec<ScopeId>>>,
+    pub shared_context: RwLock<SharedContext>,
+    pub scopes: RwLock<SlotMap<ScopeId, RwLock<Vec<ScopeProperty>>>>,
+    pub scope_parents: RwLock<SparseSecondaryMap<ScopeId, ScopeId>>,
+    pub scope_children: RwLock<SparseSecondaryMap<ScopeId, Vec<ScopeId>>>,
     #[allow(clippy::type_complexity)]
-    pub scope_contexts: RefCell<SparseSecondaryMap<ScopeId, HashMap<TypeId, Box<dyn Any>>>>,
+    pub scope_contexts: RwLock<SparseSecondaryMap<ScopeId, HashMap<TypeId, Box<dyn Any>>>>,
     #[allow(clippy::type_complexity)]
-    pub scope_cleanups: RefCell<SparseSecondaryMap<ScopeId, Vec<Box<dyn FnOnce()>>>>,
-    pub signals: RefCell<SlotMap<SignalId, Rc<RefCell<dyn Any>>>>,
-    pub signal_subscribers: RefCell<SecondaryMap<SignalId, RefCell<HashSet<EffectId>>>>,
-    pub effects: RefCell<SlotMap<EffectId, Rc<dyn AnyEffect>>>,
-    pub effect_sources: RefCell<SecondaryMap<EffectId, RefCell<HashSet<SignalId>>>>,
-    pub resources: RefCell<SlotMap<ResourceId, AnyResource>>,
+    pub scope_cleanups: RwLock<SparseSecondaryMap<ScopeId, Vec<Box<dyn FnOnce()>>>>,
+    pub signals: RwLock<SlotMap<SignalId, Arc<RwLock<dyn Any>>>>,
+    pub signal_subscribers: RwLock<SecondaryMap<SignalId, RwLock<HashSet<EffectId>>>>,
+    pub effects: RwLock<SlotMap<EffectId, Arc<dyn AnyEffect>>>,
+    pub effect_sources: RwLock<SecondaryMap<EffectId, RwLock<HashSet<SignalId>>>>,
+    pub resources: RwLock<SlotMap<ResourceId, AnyResource>>,
+}
+
+// track current observer thread-locally
+// because effects run synchronously, the current observer
+// *in this thread* will not change during the execution of an effect.
+// but if we track this across threads, it's possible for overlapping
+// executions to cause the stack to be out of order
+// so we store at most one current observer per runtime, per thread
+thread_local! {
+    static OBSERVER: RefCell<HashMap<RuntimeId, EffectId>> = Default::default();
+}
+
+pub(crate) struct LocalObserver {}
+
+impl LocalObserver {
+    pub fn take(runtime: RuntimeId) -> Option<EffectId> {
+        OBSERVER.with(|observer| observer.borrow_mut().remove(&runtime))
+    }
+
+    pub fn get(runtime: RuntimeId) -> Option<EffectId> {
+        OBSERVER.with(|observer| observer.borrow().get(&runtime).copied())
+    }
+
+    pub fn set(runtime: RuntimeId, effect: Option<EffectId>) {
+        OBSERVER.with(|observer| {
+            if let Some(value) = effect {
+                observer.borrow_mut().insert(runtime, value)
+            } else {
+                observer.borrow_mut().remove(&runtime)
+            }
+        });
+    }
 }
 
 impl Debug for Runtime {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("Runtime")
             .field("shared_context", &self.shared_context)
-            .field("observer", &self.observer)
             .field("scopes", &self.scopes)
             .field("scope_parents", &self.scope_parents)
             .field("scope_children", &self.scope_children)
             .field("signals", &self.signals)
             .field("signal_subscribers", &self.signal_subscribers)
-            .field("effects", &self.effects.borrow().len())
+            .field("effects", &self.effects.read().len())
             .field("effect_sources", &self.effect_sources)
             .finish()
     }
@@ -258,27 +282,27 @@ impl Runtime {
 
     pub(crate) fn create_unserializable_resource<S, T>(
         &self,
-        state: Rc<ResourceState<S, T>>,
+        state: Arc<ResourceState<S, T>>,
     ) -> ResourceId
     where
         S: Clone + 'static,
         T: 'static,
     {
         self.resources
-            .borrow_mut()
+            .write()
             .insert(AnyResource::Unserializable(state))
     }
 
     pub(crate) fn create_serializable_resource<S, T>(
         &self,
-        state: Rc<ResourceState<S, T>>,
+        state: Arc<ResourceState<S, T>>,
     ) -> ResourceId
     where
         S: Clone + 'static,
         T: Serializable + 'static,
     {
         self.resources
-            .borrow_mut()
+            .write()
             .insert(AnyResource::Serializable(state))
     }
 
@@ -291,7 +315,7 @@ impl Runtime {
         S: 'static,
         T: 'static,
     {
-        let resources = self.resources.borrow();
+        let resources = self.resources.read();
         let res = resources.get(id);
         if let Some(res) = res {
             let res_state = match res {
@@ -317,7 +341,7 @@ impl Runtime {
     /// Returns IDs for all [Resource]s found on any scope.
     pub(crate) fn all_resources(&self) -> Vec<ResourceId> {
         self.resources
-            .borrow()
+            .read()
             .iter()
             .map(|(resource_id, _)| resource_id)
             .collect()
@@ -326,7 +350,7 @@ impl Runtime {
     /// Returns IDs for all [Resource]s found on any scope, pending from the server.
     pub(crate) fn pending_resources(&self) -> Vec<ResourceId> {
         self.resources
-            .borrow()
+            .read()
             .iter()
             .filter_map(|(resource_id, res)| {
                 if matches!(res, AnyResource::Serializable(_)) {
@@ -342,7 +366,7 @@ impl Runtime {
         &self,
     ) -> FuturesUnordered<PinnedFuture<(ResourceId, String)>> {
         let f = FuturesUnordered::new();
-        for (id, resource) in self.resources.borrow().iter() {
+        for (id, resource) in self.resources.read().iter() {
             if let AnyResource::Serializable(resource) = resource {
                 f.push(resource.to_serialization_resolver(id));
             }

leptos_reactive/src/scope.rs

@@ -1,6 +1,6 @@
 #![forbid(unsafe_code)]
 use crate::{
-    runtime::{with_runtime, RuntimeId},
+    runtime::{with_runtime, LocalObserver, RuntimeId},
     EffectId, PinnedFuture, ResourceId, SignalId, SuspenseContext,
 };
 use futures::stream::FuturesUnordered;
@@ -108,7 +108,7 @@ impl Scope {
     pub fn run_child_scope<T>(self, f: impl FnOnce(Scope) -> T) -> (T, ScopeDisposer) {
         let (res, child_id, disposer) = self.runtime.run_scope_undisposed(f, Some(self));
         _ = with_runtime(self.runtime, |runtime| {
-            let mut children = runtime.scope_children.borrow_mut();
+            let mut children = runtime.scope_children.write();
             children
                 .entry(self.id)
                 .expect("trying to add a child to a Scope that has already been disposed")
@@ -145,9 +145,9 @@ impl Scope {
     /// ```
     pub fn untrack<T>(&self, f: impl FnOnce() -> T) -> T {
         with_runtime(self.runtime, |runtime| {
-            let prev_observer = runtime.observer.take();
+            let prev_observer = LocalObserver::take(self.runtime);
             let untracked_result = f();
-            runtime.observer.set(prev_observer);
+            LocalObserver::set(self.runtime, prev_observer);
             untracked_result
         })
         .expect("tried to run untracked function in a runtime that has been disposed")
@@ -167,7 +167,7 @@ impl Scope {
         _ = with_runtime(self.runtime, |runtime| {
             // dispose of all child scopes
             let children = {
-                let mut children = runtime.scope_children.borrow_mut();
+                let mut children = runtime.scope_children.write();
                 children.remove(self.id)
             };
 
@@ -182,7 +182,7 @@ impl Scope {
             }
 
             // run cleanups
-            if let Some(cleanups) = runtime.scope_cleanups.borrow_mut().remove(self.id) {
+            if let Some(cleanups) = runtime.scope_cleanups.write().remove(self.id) {
                 for cleanup in cleanups {
                     cleanup();
                 }
@@ -190,34 +190,34 @@ impl Scope {
 
             // remove everything we own and run cleanups
             let owned = {
-                let owned = runtime.scopes.borrow_mut().remove(self.id);
-                owned.map(|owned| owned.take())
+                let owned = runtime.scopes.write().remove(self.id);
+                owned.map(|owned| std::mem::take(&mut *owned.write()))
             };
             if let Some(owned) = owned {
                 for property in owned {
                     match property {
                         ScopeProperty::Signal(id) => {
                             // remove the signal
-                            runtime.signals.borrow_mut().remove(id);
-                            let subs = runtime.signal_subscribers.borrow_mut().remove(id);
+                            runtime.signals.write().remove(id);
+                            let subs = runtime.signal_subscribers.write().remove(id);
 
                             // each of the subs needs to remove the signal from its dependencies
                             // so that it doesn't try to read the (now disposed) signal
                             if let Some(subs) = subs {
-                                let source_map = runtime.effect_sources.borrow();
-                                for effect in subs.borrow().iter() {
+                                let source_map = runtime.effect_sources.read();
+                                for effect in subs.read().iter() {
                                     if let Some(effect_sources) = source_map.get(*effect) {
-                                        effect_sources.borrow_mut().remove(&id);
+                                        effect_sources.write().remove(&id);
                                     }
                                 }
                             }
                         }
                         ScopeProperty::Effect(id) => {
-                            runtime.effects.borrow_mut().remove(id);
-                            runtime.effect_sources.borrow_mut().remove(id);
+                            runtime.effects.write().remove(id);
+                            runtime.effect_sources.write().remove(id);
                         }
                         ScopeProperty::Resource(id) => {
-                            runtime.resources.borrow_mut().remove(id);
+                            runtime.resources.write().remove(id);
                         }
                     }
                 }
@@ -227,18 +227,18 @@ impl Scope {
 
     pub(crate) fn with_scope_property(&self, f: impl FnOnce(&mut Vec<ScopeProperty>)) {
         _ = with_runtime(self.runtime, |runtime| {
-            let scopes = runtime.scopes.borrow();
+            let scopes = runtime.scopes.read();
             let scope = scopes
                 .get(self.id)
                 .expect("tried to add property to a scope that has been disposed");
-            f(&mut scope.borrow_mut());
+            f(&mut scope.write());
         })
     }
 
     /// Returns the the parent Scope, if any.
     pub fn parent(&self) -> Option<Scope> {
         with_runtime(self.runtime, |runtime| {
-            runtime.scope_parents.borrow().get(self.id).copied()
+            runtime.scope_parents.read().get(self.id).copied()
         })
         .ok()
         .flatten()
@@ -255,7 +255,7 @@ impl Scope {
 /// are invalidated.
 pub fn on_cleanup(cx: Scope, cleanup_fn: impl FnOnce() + 'static) {
     _ = with_runtime(cx.runtime, |runtime| {
-        let mut cleanups = runtime.scope_cleanups.borrow_mut();
+        let mut cleanups = runtime.scope_cleanups.write();
         let cleanups = cleanups
             .entry(cx.id)
             .expect("trying to clean up a Scope that has already been disposed")
@@ -327,7 +327,7 @@ impl Scope {
         use futures::StreamExt;
 
         _ = with_runtime(self.runtime, |runtime| {
-            let mut shared_context = runtime.shared_context.borrow_mut();
+            let mut shared_context = runtime.shared_context.write();
             let (tx, mut rx) = futures::channel::mpsc::unbounded();
 
             create_isomorphic_effect(*self, move |_| {
@@ -350,12 +350,12 @@ impl Scope {
         })
     }
 
-    /// The set of all HTML fragments current pending, by their keys (see [Self::current_fragment_key]).
+    /// The set of all HTML fragments currently pending.
     /// Returns a tuple of the hydration ID of the previous element, and a pinned `Future` that will yield the
     /// `<Suspense/>` HTML when all resources are resolved.
     pub fn pending_fragments(&self) -> HashMap<String, (String, PinnedFuture<String>)> {
         with_runtime(self.runtime, |runtime| {
-            let mut shared_context = runtime.shared_context.borrow_mut();
+            let mut shared_context = runtime.shared_context.write();
             std::mem::take(&mut shared_context.pending_fragments)
         })
         .unwrap_or_default()

leptos_reactive/src/signal.rs

@@ -1,7 +1,7 @@
 #![forbid(unsafe_code)]
 use crate::{
     debug_warn,
-    runtime::{with_runtime, RuntimeId},
+    runtime::{with_runtime, LocalObserver, RuntimeId},
     Runtime, Scope, ScopeProperty, UntrackedGettableSignal, UntrackedSettableSignal,
 };
 use cfg_if::cfg_if;
@@ -246,7 +246,9 @@ where
 
     #[cfg(feature = "hydrate")]
     pub(crate) fn subscribe(&self) {
-        _ = with_runtime(self.runtime, |runtime| self.id.subscribe(runtime))
+        _ = with_runtime(self.runtime, |runtime| {
+            self.id.subscribe(self.runtime, runtime)
+        })
     }
 
     /// Clones and returns the current value of the signal, and subscribes
@@ -286,14 +288,17 @@ where
     /// Applies the function to the current Signal, if it exists, and subscribes
     /// the running effect.
     pub(crate) fn try_with<U>(&self, f: impl FnOnce(&T) -> U) -> Result<U, SignalError> {
-        match with_runtime(self.runtime, |runtime| self.id.try_with(runtime, f)) {
+        match with_runtime(self.runtime, |runtime| {
+            self.id.try_with(self.runtime, runtime, f)
+        }) {
             Ok(Ok(v)) => Ok(v),
             Ok(Err(e)) => Err(e),
             Err(_) => Err(SignalError::RuntimeDisposed),
         }
     }
 
-    /// Generates a [Stream] that emits the new value of the signal whenever it changes.
+    /// Generates a [Stream](futures::stream::Stream) that emits the new value of the signal
+    /// whenever it changes.
     pub fn to_stream(&self) -> impl Stream<Item = T>
     where
         T: Clone,
@@ -1096,7 +1101,8 @@ where
         )
     }
 
-    /// Generates a [Stream] that emits the new value of the signal whenever it changes.
+    /// Generates a [Stream](futures::stream::Stream) that emits the new value of the signal
+    /// whenever it changes.
     #[cfg_attr(
         debug_assertions,
         instrument(
@@ -1167,20 +1173,20 @@ pub(crate) enum SignalError {
 }
 
 impl SignalId {
-    pub(crate) fn subscribe(&self, runtime: &Runtime) {
+    pub(crate) fn subscribe(&self, runtime_id: RuntimeId, runtime: &Runtime) {
         // add subscriber
-        if let Some(observer) = runtime.observer.get() {
+        if let Some(observer) = LocalObserver::get(runtime_id) {
             // add this observer to the signal's dependencies (to allow notification)
-            let mut subs = runtime.signal_subscribers.borrow_mut();
+            let mut subs = runtime.signal_subscribers.write();
             if let Some(subs) = subs.entry(*self) {
-                subs.or_default().borrow_mut().insert(observer);
+                subs.or_default().write().insert(observer);
             }
 
             // add this signal to the effect's sources (to allow cleanup)
-            let mut effect_sources = runtime.effect_sources.borrow_mut();
+            let mut effect_sources = runtime.effect_sources.write();
             if let Some(effect_sources) = effect_sources.entry(observer) {
                 let sources = effect_sources.or_default();
-                sources.borrow_mut().insert(*self);
+                sources.write().insert(*self);
             }
         }
     }
@@ -1195,7 +1201,7 @@ impl SignalId {
     {
         // get the value
         let value = {
-            let signals = runtime.signals.borrow();
+            let signals = runtime.signals.read();
             match signals.get(*self).cloned().ok_or(SignalError::Disposed) {
                 Ok(s) => Ok(s),
                 Err(e) => {
@@ -1204,12 +1210,13 @@ impl SignalId {
                 }
             }
         }?;
-        let value = value.try_borrow().unwrap_or_else(|e| {
-            debug_warn!(
-                "Signal::try_with_no_subscription failed on Signal<{}>. It seems you're trying to read the value of a signal within an effect caused by updating the signal.",
+        let value = value.try_read().unwrap_or_else(|| {
+            panic!(
+                "Signal::try_with_no_subscription failed on Signal<{}>. \
+                It seems you're trying to read the value of a signal within an effect \
+                caused by updating the signal.",
                 std::any::type_name::<T>()
             );
-            panic!("{e}");
         });
         let value = value
             .downcast_ref::<T>()
@@ -1219,13 +1226,14 @@ impl SignalId {
 
     pub(crate) fn try_with<T, U>(
         &self,
+        runtime_id: RuntimeId,
         runtime: &Runtime,
         f: impl FnOnce(&T) -> U,
     ) -> Result<U, SignalError>
     where
         T: 'static,
     {
-        self.subscribe(runtime);
+        self.subscribe(runtime_id, runtime);
 
         self.try_with_no_subscription(runtime, f)
     }
@@ -1244,12 +1252,14 @@ impl SignalId {
         .expect("tried to access a signal in a runtime that has been disposed")
     }
 
-    pub(crate) fn with<T, U>(&self, runtime: RuntimeId, f: impl FnOnce(&T) -> U) -> U
+    pub(crate) fn with<T, U>(&self, runtime_id: RuntimeId, f: impl FnOnce(&T) -> U) -> U
     where
         T: 'static,
     {
-        with_runtime(runtime, |runtime| self.try_with(runtime, f).unwrap())
-            .expect("tried to access a signal in a runtime that has been disposed")
+        with_runtime(runtime_id, |runtime| {
+            self.try_with(runtime_id, runtime, f).unwrap()
+        })
+        .expect("tried to access a signal in a runtime that has been disposed")
     }
 
     fn update_value<T, U>(&self, runtime: RuntimeId, f: impl FnOnce(&mut T) -> U) -> Option<U>
@@ -1258,11 +1268,11 @@ impl SignalId {
     {
         with_runtime(runtime, |runtime| {
             let value = {
-                let signals = runtime.signals.borrow();
+                let signals = runtime.signals.read();
                 signals.get(*self).cloned()
             };
             if let Some(value) = value {
-                let mut value = value.borrow_mut();
+                let mut value = value.write();
                 if let Some(value) = value.downcast_mut::<T>() {
                     Some(f(value))
                 } else {
@@ -1298,14 +1308,14 @@ impl SignalId {
             // notify subscribers
             if updated.is_some() {
                 let subs = {
-                    let subs = runtime.signal_subscribers.borrow();
+                    let subs = runtime.signal_subscribers.read();
                     let subs = subs.get(*self);
-                    subs.map(|subs| subs.borrow().clone())
+                    subs.map(|subs| subs.read().clone())
                 };
                 if let Some(subs) = subs {
                     for sub in subs {
                         let effect = {
-                            let effects = runtime.effects.borrow();
+                            let effects = runtime.effects.read();
                             effects.get(sub).cloned()
                         };
                         if let Some(effect) = effect {

leptos_reactive/src/signal_wrappers_read.rs

@@ -574,6 +574,12 @@ impl<T> From<Memo<T>> for MaybeSignal<T> {
     }
 }
 
+impl<T> From<Signal<T>> for MaybeSignal<T> {
+    fn from(value: Signal<T>) -> Self {
+        Self::Dynamic(value)
+    }
+}
+
 #[cfg(not(feature = "stable"))]
 impl<T> FnOnce<()> for MaybeSignal<T>
 where

leptos_reactive/tests/untracked.rs

@@ -19,7 +19,7 @@ fn untracked_set_doesnt_trigger_effect() {
         create_isomorphic_effect(cx, {
             let b = b.clone();
             move |_| {
-                let formatted = format!("Value is {}", a());
+                let formatted = format!("Value is {}", a.get());
                 *b.borrow_mut() = formatted;
             }
         });
@@ -52,7 +52,7 @@ fn untracked_get_doesnt_trigger_effect() {
         create_isomorphic_effect(cx, {
             let b = b.clone();
             move |_| {
-                let formatted = format!("Values are {} and {}", a(), a2.get_untracked());
+                let formatted = format!("Values are {} and {}", a.get(), a2.get_untracked());
                 *b.borrow_mut() = formatted;
             }
         });

leptos_server/src/lib.rs

@@ -28,7 +28,7 @@
 //!
 //! ### `#[server]`
 //!
-//! The [`#[server]` macro](leptos::leptos_macro::server) allows you to annotate a function to
+//! The [`#[server]`](https://docs.rs/leptos/latest/leptos/attr.server.html) macro allows you to annotate a function to
 //! indicate that it should only run on the server (i.e., when you have an `ssr` feature in your
 //! crate that is enabled).
 //!
@@ -326,9 +326,19 @@ where
         let mut write = REGISTERED_SERVER_FUNCTIONS
             .write()
             .map_err(|e| ServerFnError::Registration(e.to_string()))?;
-        write.insert(Self::url(), run_server_fn);
+        let prev = write.insert(Self::url(), run_server_fn);
 
-        Ok(())
+        // if there was already a server function with this key,
+        // return Err
+        match prev {
+            Some(_) => Err(ServerFnError::Registration(format!(
+                "There was already a server function registered at {:?}. \
+                This can happen if you use the same server function name in two different modules
+                on `stable` or in `release` mode.",
+                Self::url()
+            ))),
+            None => Ok(()),
+        }
     }
 }
 

meta/src/lib.rs

@@ -34,8 +34,16 @@
 //!   }
 //!
 //! }
-//!
 //! ```
+//! # Feature Flags
+//! - `csr` Client-side rendering: Generate DOM nodes in the browser
+//! - `ssr` Server-side rendering: Generate an HTML string (typically on the server)
+//! - `hydrate` Hydration: use this to add interactivity to an SSRed Leptos app
+//! - `stable` By default, Leptos requires `nightly` Rust, which is what allows the ergonomics
+//!   of calling signals as functions. Enable this feature to support `stable` Rust.
+//!
+//! **Important Note:** You must enable one of `csr`, `hydrate`, or `ssr` to tell Leptos
+//! which mode your app is operating in.
 
 use cfg_if::cfg_if;
 use std::{

router/src/lib.rs

@@ -180,6 +180,16 @@
 //!   }
 //! }
 //! ```
+//!
+//! # Feature Flags
+//! - `csr` Client-side rendering: Generate DOM nodes in the browser
+//! - `ssr` Server-side rendering: Generate an HTML string (typically on the server)
+//! - `hydrate` Hydration: use this to add interactivity to an SSRed Leptos app
+//! - `stable` By default, Leptos requires `nightly` Rust, which is what allows the ergonomics
+//!   of calling signals as functions. Enable this feature to support `stable` Rust.
+//!
+//! **Important Note:** You must enable one of `csr`, `hydrate`, or `ssr` to tell Leptos
+//! which mode your app is operating in.
 
 #![cfg_attr(not(feature = "stable"), feature(auto_traits))]
 #![cfg_attr(not(feature = "stable"), feature(negative_impls))]