svoid tok_moduleClassDecls(L<S> tok) {
  int i;
  jreplace(tok, "module <id> {", "module $2 extends DynModule {");
  while ((i = jfind(tok, "module <id>")) >= 0) {
    int j = findEndOfBlock(tok, indexOf(tok, "{", i))-1;
    S name = tok.get(i+2);
    tok.set(i, "sclass");
    tokAppend(tok, j, "\nsbool _moduleClass_" + name + ";"); // just a marker to quickly find module classes
    reTok(tok, j, j+1);
  }
}