PHPMailer\PHPMailer

PHPMailer::isMail() │ public │ WP 1.0

{} It's a method of the class: PHPMailer{}

No Hooks.

Return

null. Nothing.

Usage

$PHPMailer = new PHPMailer();
$PHPMailer->isMail();

Code of PHPMailer::isMail() WP 6.0

wp-includes/PHPMailer/PHPMailer.php 
public function isMail()
{
    $this->Mailer = 'mail';
}