add readmes

packages/signals/README.md

@@ -0,0 +1,56 @@
+# Dioxus Signals
+
+Dioxus Signals is an ergonomic Copy runtime for data with local subscriptions in Dioxus.
+
+## Copy Data
+
+All signals implement Copy, even if the inner value does not implement copy. This makes it easy to move any data into futures or children.
+
+```rust
+fn App(cx: Scope) -> Element {
+    let signal = use_signal(cx, || "hello world".to_string());
+
+    spawn(async move {
+        // signal is Copy even though String is not copy
+        signal
+    });
+
+    render! {
+        "{signal}"
+    }
+}
+```
+
+## Local Subscriptions
+
+Signals will only subscribe to components when you read from the signal in that component. It will never subscribe to a component when reading data in a future or event handler.
+
+```rust
+fn app(cx: Scope) -> Element {
+    // Because signal is never read in this component, this component will not rerun when the signal changes
+    let signal = use_signal(cx, || 0);
+
+    render! {
+        onclick: move |_| {
+            *signal.write() += 1;
+        }
+        for id in 0..10 {
+            Child {
+                signal: signal,
+            }
+        }
+    }
+}
+
+#[derive(Props, Clone, PartialEq)]
+struct ChildProps {
+    signal: Signal<usize>,
+}
+
+fn Child(cx: Scope<ChildProps>) -> Element {
+    // This component does read from the signal, so when the signal changes it will rerun
+    render! {
+        "{cx.props.signal}"
+    }
+}
+```

packages/signals/src/lib.rs

@@ -1,3 +1,6 @@
+#![doc = include_str!("../README.md")]
+#![warn(missing_docs)]
+
 mod rt;
 pub use rt::*;
 mod effect;