static void forstat (LexState *ls, int line) {
  /* forstat -> FOR (fornum | forlist) END */
  FuncState *fs = ls->fs;
  TString *varname;
  BlockCnt bl;
  enterblock(fs, &bl, 1);  /* scope for loop and control variables */
  luaX_next(ls);  /* skip 'for' */
  varname = str_checkname(ls);  /* first variable name */
  switch (ls->t.token) {
    case '=': fornum(ls, varname, line); break;
    case ',': case TK_IN: forlist(ls, varname); break;
    default: luaX_syntaxerror(ls, "'=' or 'in' expected");
  }
  check_match(ls, TK_END, TK_FOR, line);
  leaveblock(fs);  /* loop scope ('break' jumps to this point) */
}