i found this mini project online but the arduino program wouldn't execute and i couldn't figure out the problem,here is the code and the error is (exit status 1
'tmElements_t' does not name a type) and the link of the project is bellow the code please help
#include <DS1307RTC.h>
#include <Timer.h>
#include <TM1637Display.h>
#include <Wire.h>
/****************************************************************
* *
* IKEA DUKTIG clock/timer - Roald Hendriks, January 2018 *
* *
* Hardware: Arduino Uno R3 / Arduino Nano *
* LEDstrips (in oven and over counter) *
* DS3231 SDA analog pin4, SCL analog pin5 *
* TM1637 4 digit LED Display *
* 4 buttons (+, -, start, stop) *
* Buzzer *
* *
****************************************************************
// Segments for showing BEEP
const uint8_t SEG_BEEP[] = {
SEG_A | SEG_B | SEG_C | SEG_D | SEG_E | SEG_F | SEG_G, // B
SEG_A | SEG_D | SEG_E | SEG_F | SEG_G, // E
SEG_A | SEG_D | SEG_E | SEG_F | SEG_G, // E
SEG_A | SEG_B | SEG_E | SEG_F | SEG_G, // P
};
// Definition of all digital pins
// ***** Button input pins *****
// + Button
const int PlusButtonPin = 13;
// - Button
const int MinusButtonPin = 12;
// Start Button
const int StartButtonPin = 11;
// Stop Button
const int StopButtonPin = 10;
// ***** Output pins *****
// Buzzer
const int BuzzerPin = 4;
// LED-strip in oven
const int OvenLEDPin = 5;
// TM1637 clock pin
const int TM1637CLKPin = 8;
// TM1637 data pin
const int TM1637DataPin = 7;
// PWM LED brightness
const int intLEDBrightness = 200;
// Create TM1637 object
TM1637Display display(TM1637CLKPin,TM1637DataPin);
// Create RTC time object
tmElements_t RTC_time;
// Create RTC timer objects to hold the timer
// prevTimes is used to determine whether the timer has changed
tmElements_t Timer, prevTimer;
}