function Ext_GetMainIdx() {
		if ( ($this->ExtInfo!==false) && isset($this->ExtInfo['main']) ) {
			return $this->FileGetIdx($this->ExtInfo['main']);
		} else {
			return false;
		}
	}
function Ext_GetMainIdx() {
		if ( ($this->ExtInfo!==false) && isset($this->ExtInfo['main']) ) {
			return $this->FileGetIdx($this->ExtInfo['main']);
		} else {
			return false;
		}
	}
function Ext_GetMainIdx ( ) { if ( ( $ this -> ExtInfo !== false ) && isset ( $ this -> ExtInfo [ 'main' ] ) ) { return $ this -> FileGetIdx ( $ this -> ExtInfo [ 'main' ] ) ; } else { return false ; } }
Return the idx of the main document, if any.
Return the idx of the main document if any .