void (PsiFile file, CommonElement.Visitor visitor) { if (file instanceof RncFile) { final Grammar grammar = ((RncFile)file).getGrammar(); if (grammar != null) { grammar.acceptChildren(visitor); } } else if (file instanceof XmlFile) { final DomManager mgr = DomManager.getDomManager(file.getProject()); final DomFileElement<RngGrammar> element = mgr.getFileElement((XmlFile)file, RngGrammar.class); if (element != null) { element.getRootElement().acceptChildren(visitor); } } }