public function setAttr($attr, $value) {
		$this->_attrs[$attr] = trim($value);
		$this->_tagCached    = null;
		
		return $this;
	}
public function setAttr($attr, $value) {
		$this->_attrs[$attr] = trim($value);
		$this->_tagCached    = null;
		
		return $this;
	}
public function setAttr ( $ attr , $ value ) { $ this -> _attrs [ $ attr ] = trim ( $ value ) ; $ this -> _tagCached = null ; return $ this ; }
Set the tag's attribute

@param  string $attr
@param  string $value
@return Tag
Set the tag s attribute