66   protected $cached = array();  variable in Swift_Message_Headers
82       foreach (array_keys($this->cached) as $k) $this->cached[$k] = null;
101     foreach (array_keys($this->cached) as $k)
103       $this->cached[$k] = null;
119     $this->cached[$lname] = null;
168       unset($this->cached[$lname]);
276     $this->cached[$lheader] = null;
377     if ($this->cached[$lname] !== null) return $this->cached[$lname];
472     $this->cached[$lname] = implode("," . $this->LE . " ", $encoded_value);
475 …if (!empty($this->attributes[$lname])) $this->cached[$lname] .= $this->buildAttributes($this->cach…
477     return $this->cached[$lname];