private static function index_blocks() { $block_index = array(); while ($info = HCImport::read_next_block()) { if (count($block_index) == 0 && $info['type'] != 'STAK') { throw new Exception("Not a stack."); } if (!isset($block_index[$info['type']])) { $block_index[$info['type']] = array(); } $block_index[$info['type']][$info['id']] = $info; } HCImport::$block_index = $block_index; }