Function Servo.attach not able to access servo object - c++

Question

Im writing some code for a arduino project and in the SHOOTER::LOADERclass, when i try to declare the servo objects,this is the code:
#include <Servo.h>
char t;
const bool DEBUG = true;
// Defined variables for loader class
template <typename T_ty> struct TypeInfo {
static const char * name;
};
template <typename T_ty> const char * TypeInfo<T_ty>::name = "unknown";
#define TYPE_NAME(var) TypeInfo< typeof(var) >::name
#define MAKE_TYPE_INFO(type) template <> const char * TypeInfo<type>::name = #type;
MAKE_TYPE_INFO( int )
MAKE_TYPE_INFO( float )
MAKE_TYPE_INFO( short )
MAKE_TYPE_INFO( String )
MAKE_TYPE_INFO( char )
MAKE_TYPE_INFO( byte )
class DEBUG;
class MOTOR;
class SHOOTER;
class COMM;
class DEBUG
{
public:
static void print(int argCount, ...) {
if (::DEBUG) {
return ;
}
va_list args;
va_start(args, argCount);
for (int i = 0; i < argCount; i++) {
String arg = va_arg(args, String);
Serial.print(arg);
}
Serial.println();
va_end(args);
}
};
class MOTOR
{
protected:
static const int LEFT_FRONT = 13;
static const int LEFT_REAR = 12;
static const int RIGHT_FRONT = 11;
static const int RIGHT_REAR = 10;
public:
MOTOR() {
pinMode(LEFT_FRONT, OUTPUT);
pinMode(LEFT_REAR, OUTPUT);
pinMode(RIGHT_FRONT, OUTPUT);
pinMode(RIGHT_REAR, OUTPUT);
}
static void motor_control(int lf = LOW, int lr = LOW, int rf = LOW, int rr = LOW) {
digitalWrite(LEFT_FRONT, lf);
digitalWrite(LEFT_REAR, lr);
digitalWrite(RIGHT_FRONT, rf);
digitalWrite(RIGHT_REAR, rr);
}
};
class SHOOTER
{
protected:
static const int LOADER1 = 5;
static const int LOADER2 = 6;
public:
class LOADER {
public:
static const int servo1 = 3;
static const int servo2 = 4;
static Servo l1;
static Servo l2;
static void set(float p) {
l1.write(p);
l2.write(p);
}
static void load() {
for (float p = 0; p <= 90 ; p += 0.25) {
set(p);
delay(15);
}
for (float p = 90 ; p >= 0 ; p -= 0.25) {
set(p);
delay(15);
}
}
};
SHOOTER() {
pinMode(LOADER1, OUTPUT);
pinMode(LOADER2, OUTPUT);
}
};
void setup() {
MOTOR motor;
SHOOTER shooter;
SHOOTER::LOADER::l1.attach(SHOOTER::LOADER::servo1);
SHOOTER::LOADER::l2.attach(SHOOTER::LOADER::servo2);
pinMode(9, OUTPUT); //Led
Serial.begin(9600);
}
void loop() {
if (Serial.available()) {
t = Serial.read();
if (isdigit(t)) {
t = (int) t;
Serial.print(t);
Serial.print(", ");
Serial.print(TYPE_NAME(t));
} else {
Serial.print(t);
Serial.print(", ");
Serial.print(TYPE_NAME(t));
}
Serial.println();
}
if (t == 'F') { //move forward(all motors rotate in forward direction)
MOTOR::motor_control(HIGH, LOW, HIGH);
}
else if (t == 'B') { //move reverse (all motors rotate in reverse direction)
MOTOR::motor_control(LOW, HIGH, LOW, HIGH);
}
else if (t == 'L') { //turn right (left side motors rotate in forward direction, right side motors doesn't rotate)
MOTOR::motor_control(LOW, LOW, HIGH);
}
else if (t == 'R') { //turn left (right side motors rotate in forward direction, left side motors doesn't rotate)
MOTOR::motor_control(HIGH);
}
else if (t == 'W') { //turn led on or off)
digitalWrite(9, HIGH);
}
else if (t == 'w') {
digitalWrite(9, LOW);
}
else if (t == 'S') { //STOP (all motors stop)
MOTOR::motor_control();
}
}
I get the following error
Arduino: 1.8.19 (Linux), Board: "Arduino Uno"
/tmp/ccgiae58.ltrans0.ltrans.o: In function `attach':
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:240: undefined reference to `SHOOTER::LOADER::l1'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:242: undefined reference to `SHOOTER::LOADER::l1'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:244: undefined reference to `SHOOTER::LOADER::l1'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:245: undefined reference to `SHOOTER::LOADER::l1'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:250: undefined reference to `SHOOTER::LOADER::l1'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:240: undefined reference to `SHOOTER::LOADER::l2'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:242: undefined reference to `SHOOTER::LOADER::l2'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:244: undefined reference to `SHOOTER::LOADER::l2'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:245: undefined reference to `SHOOTER::LOADER::l2'
/app/Arduino/libraries/Servo/src/avr/Servo.cpp:250: undefined reference to `SHOOTER::LOADER::l2'
collect2: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino Uno.
it seemed that the servo.attach function could not access the l1 and l2 objects, so i tried defineing them in the global scope
#include <Servo.h>
Servo l1;
Servo l2;
// the usual declaratins
void setup(){
l1.attach(4);
l2.attach(5);
//everything else the same as previously
}
tho it did solve the error, i want to know how i can declare them inside the LOADER class itself