Updating a couple examples

examples/wasm-in-wasm/src/lib.rs

@@ -19,18 +19,19 @@ const WASM: &[u8] = include_bytes!("add.wasm");
 pub fn run() -> Result<(), JsValue> {
     console_log!("instantiating a new wasm module directly");
 
-    // Note that `Uint8Array::view` this is somewhat dangerous (hence the
+    // Note that `Uint8Array::view` is somewhat dangerous (hence the
     // `unsafe`!). This is creating a raw view into our module's
     // `WebAssembly.Memory` buffer, but if we allocate more pages for ourself
     // (aka do a memory allocation in Rust) it'll cause the buffer to change,
     // causing the `Uint8Array` to be invalid.
     //
     // As a result, after `Uint8Array::view` we have to be very careful not to
-    // do any memory allocations before it's next used.
+    // do any memory allocations before it's dropped.
     let a = unsafe {
         let array = Uint8Array::view(WASM);
         WebAssembly::Module::new(array.as_ref())?
     };
+
     let b = WebAssembly::Instance::new(&a, &Object::new())?;
     let c = b.exports();
 

examples/webgl/src/lib.rs

@@ -39,12 +39,25 @@ pub fn start() -> Result<(), JsValue> {
 
     let buffer = context.create_buffer().ok_or("failed to create buffer")?;
     context.bind_buffer(WebGlRenderingContext::ARRAY_BUFFER, Some(&buffer));
-    let vert_array = unsafe { js_sys::Float32Array::view(&vertices) };
-    context.buffer_data_with_array_buffer_view(
-        WebGlRenderingContext::ARRAY_BUFFER,
-        &vert_array,
-        WebGlRenderingContext::STATIC_DRAW,
-    );
+
+    // Note that `Float32Array::view` is somewhat dangerous (hence the
+    // `unsafe`!). This is creating a raw view into our module's
+    // `WebAssembly.Memory` buffer, but if we allocate more pages for ourself
+    // (aka do a memory allocation in Rust) it'll cause the buffer to change,
+    // causing the `Float32Array` to be invalid.
+    //
+    // As a result, after `Float32Array::view` we have to be very careful not to
+    // do any memory allocations before it's dropped.
+    unsafe {
+        let vert_array = js_sys::Float32Array::view(&vertices);
+
+        context.buffer_data_with_array_buffer_view(
+            WebGlRenderingContext::ARRAY_BUFFER,
+            &vert_array,
+            WebGlRenderingContext::STATIC_DRAW,
+        );
+    }
+
     context.vertex_attrib_pointer_with_i32(0, 3, WebGlRenderingContext::FLOAT, false, 0, 0);
     context.enable_vertex_attrib_array(0);