From 75efbc27201b227507567e46c33f5d0ca944510d Mon Sep 17 00:00:00 2001
From: Justin Poehnelt <jpoehnelt@google.com>
Date: Mon, 8 Jul 2024 15:04:38 -0600
Subject: [PATCH] post: modify webassembly code

---
 src/posts/apps-script-async-await.md | 36 +++++++++++++---------------
 1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/src/posts/apps-script-async-await.md b/src/posts/apps-script-async-await.md
index 171cb96c..7ea9f4bf 100644
--- a/src/posts/apps-script-async-await.md
+++ b/src/posts/apps-script-async-await.md
@@ -66,7 +66,7 @@ async function main() {
 }
 ```
 
-This leads to an interesting discovery, the entry function can be `async` and the `await` keyword can be used. But can I use a top level await?
+This leads to an interesting discovery, the entry function can be `async` and the `await` keyword can be used. But can I use a top-level await?
 
 ```javascript
 const promise = new Promise((resolve, reject) => {
@@ -80,7 +80,7 @@ function main() {
 }
 ```
 
-No, top level await is not supported in Apps Script and returns the following error when trying to save the script:
+No, top-level await is not supported in Apps Script and returns the following error when trying to save the script:
 
 ```sh
 Syntax error: SyntaxError: await is only valid 
@@ -94,10 +94,10 @@ There is no `unhandledRejection` error for promises in Apps Script. Combined wit
 
 ## WebAssembly in Apps Script
 
-As mentioned earlier, the only place I've seen async and await actually useful in Apps Script is with the WebAssembly API. Here is a simple example of using async and await with WebAssembly:
+As mentioned earlier, the only place I've seen `async` and `await` useful in Apps Script is with the WebAssembly API. Here is a simple example of using async and await with WebAssembly:
 
 ```javascript
-async function main() {
+  async function main() {
   let bytes = new Uint8Array(
     Utilities.base64Decode(
       'AGFzbQEAAAABBwFgAn9/AX8DAgEAB' +
@@ -107,37 +107,33 @@ async function main() {
     )
   );
 
+  const promise = WebAssembly.instantiate(bytes);
+  promise.then(() => console.log("instantiated"));
+  console.log("next");
+
   let {
     instance: {
       exports: {
         add
       }
     }
-  } = await WebAssembly.instantiate(bytes);
+  } = await promise;
 
-  console.log(add(1, 2));
+  console.log("add(1,2)", add(1, 2));
 }
 ```
 
 This output works as expected:
 
 ```sh
-11:44:38 AM	Notice	Execution started
-11:44:38 AM	Info	3
-11:44:38 AM	Notice	Execution completed
-```
-
-However, to verify that the code is actually running asynchronously, I removed the `await WebAssembly.instantiate` which results in:
-
-```javascript
-11:45:57 AM	Notice	Execution started
-11:45:58 AM	Error	
-TypeError: Cannot read properties of 
-  undefined (reading 'exports') 
-  main	@ Code.gs:6
+3:00:58 PM	Notice	Execution started
+3:00:58 PM	Info	next
+3:00:58 PM	Info	instantiated
+3:00:58 PM	Info	add(1,2) 3
+3:00:59 PM	Notice	Execution completed
 ```
 
-So, it is clear that the WebAssembly API is actually running asynchronously and populating the `instance.exports` object after the `instantiate` method is called.
+So, it is clear that the WebAssembly API is running asynchronously and not blocking the task queue.
 
 ## Conclusion