lib/mail/Mail.php
public function setGlobalSubject($subject)
    {
        if (!($subject instanceof Subject)) {
            $subject = new Subject($subject);
        }
        $this->subject = $subject;
    }
public function setGlobalSubject($subject)
    {
        if (!($subject instanceof Subject)) {
            $subject = new Subject($subject);
        }
        $this->subject = $subject;
    }
public function setGlobalSubject ( $ subject ) { if ( ! ( $ subject instanceof Subject ) ) { $ subject = new Subject ( $ subject ) ; } $ this -> subject = $ subject ; }
Add a subject to a Mail object

Note that
subjects added to Personalization objects override
global subjects.

@param string|Subject $subject Email subject
Add a subject to a Mail object