docs: add examples

this is to show how we can use closures in the mad component context. It isn't super pretty because of the async closure, so we need to show the slighly complicated syntax

Signed-off-by: kjuulh <contact@kjuulh.io>

README.md

@@ -41,3 +41,11 @@ async fn main() -> anyhow::Result<()> {
 }
 ```
 
+## Examples
+
+Can be found (here)[crates/mad/examples]
+
+- basic
+- fn
+- signals
+- error_log

crates/mad/examples/fn/main.rs

@@ -10,7 +10,7 @@ impl mad::Component for WaitServer {
         Some("WaitServer".into())
     }
 
-    async fn run(&self, cancellation: CancellationToken) -> Result<(), mad::MadError> {
+    async fn run(&self, _cancellation: CancellationToken) -> Result<(), mad::MadError> {
         let millis_wait = rand::thread_rng().gen_range(500..3000);
 
         tracing::debug!("waiting: {}ms", millis_wait);
@@ -28,9 +28,11 @@ async fn main() -> anyhow::Result<()> {
         .with_max_level(Level::TRACE)
         .init();
 
+    let item = "some item".to_string();
+
     mad::Mad::builder()
         .add(WaitServer {})
-        .add_fn(|cancel| async move {
+        .add_fn(|_cancel| async move {
             let millis_wait = 50;
 
             tracing::debug!("waiting: {}ms", millis_wait);
@@ -40,6 +42,24 @@ async fn main() -> anyhow::Result<()> {
 
             Ok(())
         })
+        .add_fn(move |_cancel| {
+            // I am an actual closure
+
+            let item = item.clone();
+
+            async move {
+                let _item = item;
+
+                let millis_wait = 50;
+
+                tracing::debug!("waiting: {}ms", millis_wait);
+
+                // Simulates a server running for some time. Is normally supposed to be futures blocking indefinitely
+                tokio::time::sleep(std::time::Duration::from_millis(millis_wait)).await;
+
+                Ok(())
+            }
+        })
         .run()
         .await?;