code: func (l *State) RawGetInt(index, key int) {
  	t := l.indexToValue(index).(*table)
  	l.apiPush(t.atInt(key))
  }
docs: // RawGetInt pushes onto the stack the value table[key] where table is the
  // value at index on the stack. The access is raw, as it doesn't invoke
  // metamethods.
  //
  // http://www.lua.org/manual/5.2/manual.html#lua_rawgeti