Add TypedFallbackShow component

README.md

@@ -11,6 +11,7 @@ Documentation for the crates is available on [Docs.rs](https://docs.rs/):
 -   [`leptos-struct-component`](https://docs.rs/leptos-struct-component/latest/leptos_struct_component/)
 -   [`leptos-struct-component-macro`](https://docs.rs/leptos-struct-component-macro/latest/leptos_struct_component_macro/)
 -   [`leptos-style`](https://docs.rs/leptos-style/latest/leptos_style/)
+-   [`leptos-typed-fallback-show`](https://docs.rs/leptos-typed-fallback-show/latest/leptos_typed_fallback_show/)
 
 ## License
 

packages/leptos-typed-fallback-show/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "leptos-typed-fallback-show"
+description = "A Show component for Leptos with typed fallback support."
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+version.workspace = true
+
+[dependencies]
+leptos.workspace = true

packages/leptos-typed-fallback-show/README.md

@@ -0,0 +1,15 @@
+# Leptos Typed Fallback Show
+
+A `Show` component for [Leptos](https://leptos.dev/) with typed fallback support.
+
+## Documentation
+
+Documentation for the crate is available on [Docs.rs](https://docs.rs/):
+
+-   [`leptos-typed-fallback-show`](https://docs.rs/leptos-typed-fallback-show/latest/leptos_typed_fallback_show/)
+
+## Rust For Web
+
+The Leptos Typed Fallback Show project is part of [Rust For Web](https://github.com/RustForWeb).
+
+[Rust For Web](https://github.com/RustForWeb) creates and ports web UI libraries for Rust. All projects are free and open source.

packages/leptos-typed-fallback-show/src/lib.rs

@@ -0,0 +1,5 @@
+//! A `Show` component for [Leptos](https://leptos.dev/) with typed fallback support.
+
+mod typed_fallback_show;
+
+pub use typed_fallback_show::*;

packages/leptos-typed-fallback-show/src/typed_fallback_show.rs

@@ -0,0 +1,26 @@
+use leptos::{either::Either, prelude::*};
+
+/// A `Show` component with typed fallback support.
+#[component]
+pub fn TypedFallbackShow<F, IV, W, C>(
+    /// The children will be shown whenever the condition in the `when` closure returns `true`.
+    children: TypedChildrenFn<C>,
+    /// A closure that returns a bool that determines whether this thing runs
+    when: W,
+    /// A closure that returns what gets rendered if the when statement is false. By default this is the empty view.
+    fallback: F,
+) -> impl IntoView
+where
+    W: Fn() -> bool + Send + Sync + 'static,
+    F: Fn() -> IV + Send + Sync + 'static,
+    IV: IntoView + 'static,
+    C: IntoView + 'static,
+{
+    let memoized_when = ArcMemo::new(move |_| when());
+    let children = children.into_inner();
+
+    move || match memoized_when.get() {
+        true => Either::Left(children()),
+        false => Either::Right(fallback().into_view()),
+    }
+}