static S snippetWithTitle_cached(S id) {
  if (!isSnippetID(id)) ret id;
  id = formatSnippetID(id);
  ret id + " - " + getSnippetTitle_cached(id);
}

static S snippetWithTitle_cached(Snippet s) {
  ret s == null ? "-" : s.id + " - " + s.title;
}