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Annotate example of using with null with good/bad #42944

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chrisdavidmills merged 2 commits into from
Jan 28, 2026
+7 −3
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Annotate example of using with null with good/bad #42944

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Annotate example of using with null with good/bad
dontcallmedom Jan 28, 2026
427f356
Improve grammar, reorder section
chrisdavidmills Jan 28, 2026
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10 changes: 7 additions & 3 deletions files/en-us/web/javascript/reference/statements/using/index.md
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Expand Up @@ -164,7 +164,7 @@ In both cases, when the scope exits, `resource2` is disposed before `resource1`.

### Optional `using`

`using` allows the variable to have value `null` or `undefined`, so the resource can be optionally present. This means you don't have to do this:
`using` allows the variable to have a value of `null` or `undefined`, so the resource can be optionally present. This means that, for example, if you are checking the availability of a resource of some kind:

```js
function acquireResource() {
Expand All @@ -175,7 +175,11 @@ function acquireResource() {
}
return new Resource();
}
```

You don't have to do this:

```js example-bad
const maybeResource = acquireResource();

if (maybeResource) {
Expand All @@ -186,9 +190,9 @@ if (maybeResource) {
}
```

But can do this:
And can instead do this:

```js
```js example-good
using resource = acquireResource();
console.log(resource?.getValue());
```
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