wp-includes/class-wp-user.php:419Retrieves the value of a property or meta key.
$keystringmixed public function get( $key ) { return $this->__get( $key ); }Introduced in 3.3.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-user.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.