[Error]a function-definition is not allowed here before '{' token

Other Hardware 3rd Party Boards
1

Here is my code

#include <Wire.h>
#include "SparkFunISL29125.h"
#include <Stepper.h>

SFE_ISL29125 RGB_sensor;

const int stepsPerRevolution = 12 ; 
Stepper myStepper(stepsPerRevolution, 14, 12, 13, 15);
int stepCount = 0; 

//Green
const byte ledg_gpio = 32;

//Blue
const byte ledb_gpio = 35;

void setup(){
  //Initialize serial communication
  Serial.begin(115200);

  //Initialize ISl29125
  RGB_sensor.init();

  //Green LED
  pinMode(ledg_gpio, OUTPUT);

  //Blue LED 
  pinMode(ledb_gpio, OUTPUT);
}

void setZeroPostion(){
  unsigned long previousMillis = 0;
  const long interval = 1000;
  unsigned long currentMillis = millis();
  myStepper.setSpeed(500);
  myStepper.step(1);
  bool motor_state = true;
  while (motor_state) {
    unsigned int green = RGB_sensor.readGreen();
    if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
     
    if (green == 65535){
      motor_state = false;
    }
  myStepper.step(0);
  }
}

void loop(){
  setZeroPosition();
}

And I got an error "a function-definition is not allowed here before '{' token" at void loop

2

Edit

#include <Wire.h>
#include "SparkFunISL29125.h"
#include <Stepper.h>

SFE_ISL29125 RGB_sensor;

const int stepsPerRevolution = 12 ; 
Stepper myStepper(stepsPerRevolution, 14, 12, 13, 15);
int stepCount = 0; 

//Green
const byte ledg_gpio = 32;

//Blue
const byte ledb_gpio = 35;

void setup(){
  //Initialize serial communication
  Serial.begin(115200);

  //Initialize ISl29125
  RGB_sensor.init();

  //Green LED
  pinMode(ledg_gpio, OUTPUT);

  //Blue LED 
  pinMode(ledb_gpio, OUTPUT);
}

void setZeroPosition(){
  unsigned long previousMillis = 0;
  const long interval = 1000;
  unsigned long currentMillis = millis();
  myStepper.setSpeed(500);
  myStepper.step(1);
  bool motor_state = true;
  while (motor_state) {
    unsigned int green = RGB_sensor.readGreen();
    if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
     
    if (green == 65535){
      motor_state = false;
    }
  myStepper.step(0);
  }
}

void loop(){
  setZeroPosition();
}
3

Your setZeroPosition function is missing a closing brace.

4

Thank you so much