With Javascript function JSDocs, I've seen two different syntaxes for documenting the return values that can be nullable.

Let's say we have this function:

const getTitle = () => { // Can return string or null };

For this, which of the following JSDocs is correct:

1. @returns {?string}
2. @returns [string]
3. Something else?

With Javascript function JSDocs, I've seen two different syntaxes for documenting the return values that can be nullable.

Let's say we have this function:

const getTitle = () => { // Can return string or null };

For this, which of the following JSDocs is correct:

1. @returns {?string}
2. @returns [string]
3. Something else?

• javascript
• jsdoc

• 1 I wrote this cheat sheet to help me with this. Sharing in case it's useful. – custommander Commented Nov 9, 2021 at 8:33

1 Answer 1

You can do this in two ways, the first preferred:

@returns {?string}

@returns {string|null}