minor fixes

Author: iliakan

1-js/11-async/08-async-await/04-promise-all-failure/solution.md

@@ -82,7 +82,32 @@ function customPromiseAllWait(promises){
 
 Now `await customPromiseAllWait(...)` will stall the execution until all queries are processed.
 
-This is a more reliable approach.
+This is a more reliable approach, as it guarantees a predictable execution flow.
 
-Lastly, if we'd like to know about all the errors, e.g. for logging purposes, we can use `Promise.allSettled`.
+Lastly, if we'd like to process all errors, we can use either use `Promise.allSettled` or write a wrapper around it to gathers all errors in a single [AggregateError](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError) object and rejects with it.
 
+```js
+// wait for all promises to settle
+// return results if no errors
+// throw AggregateError with all errors if any
+functionallOrAggregateError(promises){
+returnPromise.allSettled(promises).then(results=>{
+consterrors= [];
+constvalues= [];
+
+results.forEach((res, i) =>{
+if (res.status==='fulfilled'){
+ values[i] =res.value;
+ } else{
+errors.push(res.reason);
+ }
+ });
+
+if (errors.length>0){
+thrownewAggregateError(errors, 'One or more promises failed');
+ }
+
+return values;
+ });
+}
+```