Make code example show

presentation/chapters/en-US/wasm.chapter

@@ -184,7 +184,9 @@ Calling the Javascript function:
 
 ## DOM Interaction
 
-There is a [WebPlatform crate](https://github.com/tcr/rust-webplatform) to explore and contribute to. Working with it looks like this:
+There is a [WebPlatform crate](https://github.com/tcr/rust-webplatform) to explore and contribute to.
+
+<pre><code data-source="chapters/shared/code/wasm/19.rs" data-trim="hljs rust"></code></pre>
 
 ---
 

presentation/chapters/shared/code/wasm/19.rs

@@ -0,0 +1,24 @@
+extern crate webplatform;
+
+fn main() {
+    let document = webplatform::init();
+    let body = document.element_query("body")
+        .unwrap();
+    body.html_append("\
+        <h1>This header brought to you by Rust</h1>\
+        <button>Click me!</button>\
+    ");
+
+    let button = document.element_query("button")
+        .unwrap();
+    button.on("mouseenter", move |_| {
+        println!("Mouse entered!");
+        body.html_append("<p>Mouse entered!</p>");
+    });
+    button.on("click", |_| {
+        println!("Clicked!");
+        webplatform::alert("Clicked!");
+    });
+
+    webplatform::spin();
+}