public void parse() {
            if (parsing)
                return;
            begin_parsing();
            try {
                Thread.create<void>(() => {
                    lock (context) {
                        parsing = true;
                        report.init();
                        Vala.CodeContext.push (context);
                        foreach (var file in context.get_source_files())
                            if (file.get_nodes().size == 0)
                                parser.visit_source_file (file);
                        context.check();
                        Vala.CodeContext.pop();
                        end_parsing (report);
                        parsing = false;
                    }
                }, false);
            } catch {

            }
        }